Most people who have heard of the Arian controversy have heard of it from Gibbon, or from someone repeating Gibbon. In the twenty-first chapter of the Decline and Fall, he remarks that ‘the profane of every age have derided the furious contests which the difference of a single diphthong excited between the Homoousians and the Homoiousians.’ I have done my share of deriding. It is hard not to smile at the thought of bishops hustled into exile, and of mobs fighting in the streets of Alexandria, over whether the Son of God was of the same substance as his Father or only of a similar substance. Gregory of Nyssa, who was on the winning side, complained that nothing could be done in Constantinople without a lecture. Ask a tradesman for your change, he said, and you were told about the begotten and the unbegotten. Ask the price of bread, and you learned that the Father was greater and the Son inferior. Ask whether your bath was ready, and the attendant informed you that the Son had been made out of nothing.
The joke is a good one, and I do not propose to give it up. But I have come to think that it hides more than it shows. The Arian controversy was the most important theological dispute of the fourth-century Church and one of the decisive episodes in the formation of orthodox Christianity. At its centre was a question that Christians had been asking, in one form or another, long before Arius appeared. If there is one God, what is the relationship between this God and Jesus Christ, whom Christians worshipped as Lord, called the Son of God, and associated with the divine work of creation and salvation? The New Testament supplied abundant material both for the unity of God and for the extraordinary status of Christ. What it did not supply was the technical vocabulary of later Trinitarian theology. The dispute of the fourth century arose from attempts to explain how these claims fitted together without dividing God into more than one God, and without reducing Christ to the level of an ordinary creature. Anyone who accepts the claims at all must sooner or later ask the question, and it is no discredit to the men of the fourth century that they asked it with some heat.
The name ‘Arian controversy’ is convenient but somewhat misleading. Arius gave the dispute its first shape, but the argument soon grew much larger than the teachings of one Alexandrian presbyter. Within a few years it had drawn in bishops and emperors, councils and local congregations, and rival networks of churchmen across the Roman world. After the Council of Nicaea in 325, moreover, many opponents of the Nicene settlement were not Arians in any strict sense and did not accept every proposition associated with Arius. During the middle decades of the century there were several competing parties, and the terms used by ancient polemicists make the position look tidier than it was. Writers on both sides classified their opponents under hostile labels, much as our own political journalists do when they call every opponent of the latest war an appeaser. ‘Arian’ became in time a convenient Nicene word for a wide range of positions regarded as diminishing the full divinity of the Son. Many of the men so described were indignant at the name. The bishops who met at Antioch in 341 protested that they were no followers of Arius, and asked how bishops could be supposed to follow a presbyter.
The controversy therefore needs to be understood in two ways at once. It was a theological argument about Christ, and it was a struggle over the language in which Christian doctrine could legitimately be defined. I should add that I write as a student of history and not as a theologian. I am not competent to say which party was right about the inner life of God, and I am not sure that anyone is. What I can try to explain is what each party said, why it said it, and how one of them came to win.
The Problem before Arius
Arius did not invent the question that produced the controversy. Christians had been arguing about the relationship between the Father, Son and Holy Spirit for generations. The difficulty followed from convictions already embedded in Christian worship and Scripture. Christianity inherited from Judaism an uncompromising belief in one God. At the same time, the earliest Christians spoke of Jesus in ways that placed him extraordinarily close to God. The Gospel according to John describes the Word as existing ‘in the beginning’, as being ‘with God’, and as being divine: θεὸς ἦν ὁ λόγος. Paul can speak of Christ as pre-existing and as the agent through whom creation exists. Christians prayed in his name, baptised in a formula associating Father, Son and Holy Spirit, and confessed Jesus as Lord. The practice was older than any theory of it. When the younger Pliny, as governor of Bithynia, examined some Christians in about the year 112, he reported to Trajan that their custom was to meet before dawn and sing a hymn to Christ as to a god, carmenque Christo quasi deo dicere. Two centuries later, and a few days’ journey from where Pliny wrote, the bishops would meet to decide what the quasi meant.
The intellectual problem was how these statements should be combined. If the Father and the Son were both divine, did Christianity teach two gods? If they were two names or manifestations of one divine person, how could the Gospel narratives make sense of the Father sending the Son, the Son praying to the Father, or the Father raising the Son? If the Son were subordinate to the Father, what sort of subordination was involved? It might be a distinction of relation and role. It might be that the Son was in some sense a lesser being. These are not questions that a clever sceptic thought up to embarrass the faithful. They follow from the texts, and a child who has been taught both the Shema and the Lord’s Prayer could ask them.
Third-century theologians had offered different answers. Origen of Alexandria, one of the greatest Christian intellectuals before Nicaea, taught the eternal generation of the Son from the Father and gave the Son an exalted cosmic and divine status. He also used language of subordination that later generations could interpret in different ways, and in one place he was willing to call the Son a ‘second god’. Both parties in the next century could claim him, and both did. Other theologians had reacted against doctrines that seemed to divide the Godhead. Sabellius and those who thought like him insisted so strongly on divine unity that Father and Son risked becoming modes or manifestations of one person and ceased to be distinct in any real sense. The controversy that erupted in Alexandria around 318 therefore arose within an existing debate about how monotheism and the divinity of Christ were to be reconciled. What had changed was the position of the Church. The last persecution had ended a few years before. The bishops no longer needed to stand together against the magistrate, and they had leisure to examine each other.
Arius and Alexander of Alexandria
Arius was a presbyter in Alexandria, probably born sometime around the middle of the third century, and by the account of Epiphanius a Libyan. He had charge of the church in the district called Baucalis. He was educated, ascetic and apparently an effective preacher, with enough personal following to make his dispute with his bishop a serious ecclesiastical problem. Epiphanius, who wrote half a century later and hated his memory, describes a tall, lean man of grave manner and gentle speech, dressed in a short cloak and a sleeveless tunic, and says that seven hundred consecrated virgins took his side. Our knowledge of his teaching is complicated by the survival of comparatively little of his work. Most of what he wrote was destroyed, or is preserved only in quotations by opponents. Constantine ordered his books to be burned, and a letter preserved by the historian Socrates makes it a capital offence to be found hiding one. I note in passing that this is, so far as I know, the first general order by a Christian government for the destruction of a Christian’s writings, and that it worked. What remains are fragments of letters and of a composition known as the Thalia, or ‘Banquet’, which was partly in verse and which Athanasius despised for its metre as much as for its doctrine. A later writer says that Arius also composed songs for sailors and millers and travellers to sing at their work. From these scraps the broad structure of his thought can be recovered, though we must remember that the selection was made by men who wished him to be remembered as badly as possible.
The immediate dispute arose between Arius and Alexander, bishop of Alexandria. At issue was the relation of the Son to the Father. According to Socrates, it began when Alexander lectured his clergy on the unity of the Trinity with more ambition than was prudent, and Arius thought he heard in it the old error of Sabellius. Arius wished above all to protect the uniqueness and transcendence of God the Father. God alone, in the fullest sense, was without beginning. If the Son were genuinely begotten by the Father, Arius reasoned, then the Son must owe his existence to the Father and could not possess the same underived eternity. A son who is as old as his father is not, in any sense that the word will bear, a son.
This reasoning produced the proposition for which Arius became notorious: before the Son was begotten, he did not exist. His opponents summarised it in the formula ἦν ποτε ὅτε οὐκ ἦν, ‘There was when he was not’. It is often rendered more loosely as ‘There was a time when he was not’, but the Greek has no word for time, and the insertion can obscure the point. Arius could place the generation of the Son before the creation of temporal existence itself. He was not saying that there were centuries in which the Father waited alone. He was saying that the Son’s existence had a beginning and the Father’s had none.
Arius did not regard Christ as an ordinary creature. In his own words to Alexander, the Son was ‘a perfect creature of God, but not as one of the creatures’. The Son existed before the created universe, was the Father’s supreme work, and served as the agent through whom the rest of creation came into being. He possessed a dignity unavailable to any other creature. Nevertheless, he derived his existence from the Father’s will and therefore did not share the Father’s unbegotten and eternal being. The distinction between Creator and creature placed the Son, however exalted, on the created side of the boundary. That was the proposition Alexander found unacceptable, and that Athanasius after him would spend a lifetime attacking. Alexander called together about a hundred bishops from Egypt and Libya, who condemned Arius and put him out of the Church.
What Arius Was Trying to Protect
It is easy to describe Arius as the man who denied that Jesus was God. This is too crude to explain either his theology or its appeal. Arius believed himself to be defending Christian monotheism and the genuine distinction between Father and Son. If the Son possessed exactly the same divine being as the Father, he feared one of two results. Christianity would have introduced two ultimate divine beings, which is polytheism. Or the distinction between Father and Son would collapse, which is the doctrine of Sabellius over again. He saw himself as a conservative holding the line his teachers had held, and there were learned bishops throughout the East who saw him in the same way.
He could also appeal to passages of Scripture in which the Son appears subordinate to the Father. Jesus says that ‘the Father is greater than I’ in John 14:28. Mark 13:32 appears to attribute knowledge to the Father that the Son does not possess. Proverbs 8:22, read through the traditional Christian identification of divine Wisdom with the pre-existent Christ, was particularly important. In the Greek Old Testament, Wisdom says κύριος ἔκτισέν με ἀρχὴν ὁδῶν αὐτοῦ, which is most naturally taken to mean that the Lord ‘created’ her as the beginning of his ways. The Hebrew verb is less definite, but hardly anyone in the argument could read Hebrew, and it was the Greek that counted. Such texts could be used to support the argument that the Son’s divine status was derived and was not his by nature.
The opposing case likewise rested heavily on Scripture. The opening of John’s Gospel appeared to place the Word in the eternal beginning and to identify him with divine reality. John 10:30 had Jesus say, ‘I and the Father are one.’ Thomas addresses the risen Jesus as ‘My Lord and my God’ in John 20:28. Christian baptism and worship associated Christ with God in ways difficult to reconcile with the idea that he belonged fundamentally to the created order. Each side had its list of texts, and each had an explanation of the texts on the other list. The Arian said that ‘one’ in John 10:30 meant one in will. The Nicene said that ‘greater than I’ referred to the Son in his human nature.
The controversy was therefore not a contest between people who accepted Scripture and people who rejected it. Both sides claimed biblical support. The disagreement concerned how apparently different scriptural statements should be related, and what philosophical language could legitimately be used to explain them. It is one of the oddities of the affair that the party remembered as rationalising heretics were the ones who kept asking where a particular word was to be found in the Bible.
Why Salvation Became Central to the Argument
The disagreement was more than metaphysical. For the defenders of the full divinity of Christ, the nature of salvation was at stake. This argument became especially important in Athanasius, who had attended Nicaea as Alexander’s deacon, succeeded him as bishop of Alexandria in 328, and became the most determined defender of the Nicene position.
Athanasius’s reasoning was that salvation requires more than assistance from an exalted creature. Humanity’s problem is alienation from God, with corruption and death as its consequences. If Christ belongs to the created order, he cannot by his own nature unite humanity with God or communicate divine life. A creature might teach, govern or intercede, but it cannot make other creatures participants in the divine life, because it has that life only on loan. Athanasius put the matter in a sentence that is still startling: the Word was made man that we might be made god. This is the background to the later patristic principle that only God can save. The incarnation has saving power because the Word who assumes human nature is genuinely divine. Humanity is joined to God because God himself, in the person of the Son, has entered human existence.
The argument should not be reduced to the claim that an ‘infinite sacrifice’ was required to pay an infinite debt. That belongs to later Western theories of atonement, and its classic statement is by Anselm of Canterbury, seven hundred years after Arius. English readers, brought up directly or at one remove on the theology of the Reformation, tend to assume that the Cross as payment was always the centre of the matter. The fourth-century argument was more often about participation, incorruption and deification. What Christ possesses by nature can be communicated to humanity only if Christ truly belongs to the divine being and does not merely stand at the head of creation. There was a second argument, which any congregation could follow without philosophy. Christians worshipped Christ. If Christ was a creature, they were worshipping a creature, and by their own account of the pagans that was idolatry.
From Alexandria to an Imperial Crisis
Alexander condemned Arius locally, but the controversy did not remain an Alexandrian affair. Arius appealed to sympathetic bishops elsewhere, among whom Eusebius of Nicomedia mattered most. Arius addressed him as a fellow pupil of the martyr Lucian of Antioch, and he was bishop of the city where the eastern Emperor kept his court. The other Eusebius, the historian and bishop of Caesarea, was also friendly. Letters circulated, bishops intervened, and what might otherwise have remained a regional dispute became a conflict throughout the eastern Church.
The timing was significant. Constantine had recently emerged as sole ruler of the Roman Empire after defeating Licinius in 324. He had already favoured Christianity and had intervened in the Donatist controversy in North Africa, where his councils and his soldiers had between them settled nothing. He now encountered a divided eastern Church at the moment when his political victory had reunited the Empire under one ruler. A man who believed that he owed his victories to the Christian God had reason to worry when the servants of that God were at each other’s throats.
Constantine’s first instinct seems not to have been a sophisticated theological judgement. He regarded the dispute between Alexander and Arius as an argument that ought to be settled, and sent Hosius of Cordoba to investigate and encourage reconciliation. The letter Hosius carried is preserved by Eusebius of Caesarea. It tells both men that the point at issue is small and not worth the quarrel, that such questions should never have been asked and, once asked, should never have been answered. It reads like the letter of a general who has been told that two of his officers are fighting over something in a book. When this failed, Constantine summoned a council of bishops to meet at Nicaea in Bithynia in 325.
The importance of imperial intervention should be neither exaggerated nor minimised. Constantine did not invent the theological disagreement, and he did not dictate the doctrine that emerged because he wanted a convenient imperial religion. The bishops argued intensely over questions that had arisen from their own theological traditions. But the Emperor transformed the institutional setting of the dispute. The bishops travelled to Nicaea by the public post and were fed at the public expense. They met in a hall of the palace, and Constantine opened the proceedings in person. A Christian doctrinal controversy could now be addressed by a council convened with imperial assistance, and the decisions of that council could be backed by imperial coercion. This was something new. A bishop who lost an argument in the year 250 had lost an argument. A bishop who lost one in 325 lost his see as well, and went under guard to wherever the Emperor chose to send him.
The Council of Nicaea
The Council of Nicaea met in the early summer of 325 and was attended by several hundred bishops, overwhelmingly from the eastern provinces. Its exact attendance cannot be reconstructed with certainty. Eusebius of Caesarea, who was there, speaks of more than two hundred and fifty. The traditional figure of 318 appears later, and acquired symbolic importance because it is the number of Abraham’s servants in the fourteenth chapter of Genesis. The Latin West sent only a handful, among them Hosius and two presbyters representing the aged bishop of Rome. Many of those present had been through the persecution, and the story is told that Constantine kissed the empty eye socket of the Egyptian confessor Paphnutius. The council dealt with several matters, including the calculation of Easter, a schism in Egypt, and questions of ecclesiastical discipline, the first of which was whether men who had castrated themselves might remain in the clergy. But the dispute surrounding Arius dominated its later reputation.
The resulting creed declared the Son to be ‘God from God, Light from Light, true God from true God, begotten not made’ and, most controversially, ὁμοούσιον τῷ πατρί, ‘of one substance’ or ‘of the same essence’ with the Father. It also anathematised propositions associated with Arius, including the claim that there was when the Son did not exist and that he had been made from things that previously did not exist. Only two bishops, both Libyans, refused to sign, and they went into exile with Arius. A popular novel of twenty years ago told its millions of readers that the divinity of Christ was carried at Nicaea by a narrow vote. Nobody at Nicaea doubted that Christ was divine in some sense. The question was in what sense, and the vote was not narrow.
The word homoousios was crucial because it excluded the possibility that the Son belonged to a different order of being from the Father. If the Son is homoousios with the Father, he is not a creature who merely resembles God or has been promoted to divine honour. Whatever distinction exists between Father and Son, it exists within the one divine reality. The word seems to have been chosen for the plain reason that the friends of Arius could not sign it with a private reservation, as they could sign any phrase taken from Scripture.
Yet the word created problems of its own. It was not a biblical term, and some bishops were suspicious of introducing philosophical vocabulary into a confession supposedly grounded in Scripture. It also had an ambiguous history. Gnostic writers had used it, and a council at Antioch in 268 was later said to have condemned it in connection with Paul of Samosata. Depending on how it was understood, it might suggest that Father and Son were two portions of some prior divine stuff, like two coins struck from one bar of metal, or it might suggest that they were insufficiently distinct, which was the Sabellian error again. Eusebius of Caesarea signed, and then wrote an embarrassed letter to his own church explaining what he had signed. He says that the Emperor himself proposed the word, and that it was to be understood in no bodily sense. It reads like the letter of a man who has voted for something at a party conference and must now explain himself to his constituency association. The acceptance of homoousios at Nicaea therefore did not mean that every bishop suddenly understood the Trinity in the form familiar from later theology. Athanasius himself made little use of the word for a quarter of a century.
Nicaea Did Not End the Controversy
The traditional story of the controversy can make Nicaea look like its conclusion: Arius was condemned, orthodoxy defined, and the Church then spent several decades suppressing a defeated heresy. Almost the opposite is true. Nicaea began a new phase of argument that lasted for more than half a century.
Arius himself was condemned and exiled, but he was permitted to return within a few years after presenting a formula of faith that Constantine found acceptable. Bishops who had supported him found ways of regaining imperial favour. Eusebius of Nicomedia, the most important of them, was exiled a few months after the council, was back within three years, and became influential at court. It was he who baptised Constantine shortly before the Emperor’s death in 337. The first Christian Emperor was therefore received into the Church by the leader of the party that his own council had been called to condemn. Arius had died the year before. According to Athanasius, who was not present, he was on his way to be readmitted to communion in Constantinople when he was taken ill in the street, withdrew to a public latrine, and died there with his bowels gushing out. The orthodox saw the hand of God, and told the story with an eye on the death of Judas. Gibbon remarks that those who take it literally must choose between poison and miracle.
Athanasius, meanwhile, had become bishop of Alexandria and spent much of his long episcopate in conflict with imperial and ecclesiastical opponents. He was exiled five times, by four emperors, and passed about seventeen of his forty-five years as bishop away from his see. Some of the charges against him concerned theology. Others concerned alleged violence, administrative misconduct and ecclesiastical politics. At the Council of Tyre in 335 he was accused of murdering a bishop named Arsenius and keeping the severed hand for use in sorcery. The hand was shown to the council in a box. Athanasius then produced Arsenius, alive and with both hands attached, and asked where the third had grown. What ruined him with Constantine was a different charge, that he had threatened to stop the corn fleet sailing from Alexandria to Constantinople. That the charge could be believed tells us what sort of power a bishop of Alexandria was thought to have. Nor were the accusations of violence all invented. A papyrus letter of the year 335, now in London, describes his supporters beating and imprisoning clergy of a rival Egyptian sect, and Timothy Barnes, the most severe of his modern critics, has compared his methods to those of a gangster. He was a very great man, and I should not have cared to be his opponent in an Alexandrian parish.
The disputes cannot therefore be understood solely as philosophical arguments conducted in episcopal libraries. Control of major sees, access to the Emperor and rival networks of bishops mattered enormously. So did geography. The Latin West, where few had read the Greek theologians and the Bishop of Rome gave Athanasius shelter, stood by Nicaea. Much of the Greek East did not. When a council meant to be general met at Serdica in 343, the two halves could not agree to sit in the same room.
What makes the period difficult is that opposition to Athanasius or to the word homoousios did not necessarily imply acceptance of Arius’s original theology. Many eastern bishops rejected the proposition that the Son was a creature but remained uncomfortable with Nicene terminology. Others sought alternative formulas that they believed better preserved both the divinity of the Son and his distinction from the Father. The decades after Nicaea were consequently filled with councils and creeds. Ammianus Marcellinus, a pagan army officer with no interest in the theology, complained that the crowds of bishops hurrying to and from their synods at public expense had crippled the imperial transport service.
The Importance of One Iota
The later dispute is often summarised through the famous contrast between homoousios, ‘of the same substance’, and homoiousios, ‘of similar substance’. Since the two Greek words differ by a single iota, the controversy has been mocked as an example of Christians fighting over one letter. This brings me back to Gibbon and his diphthong. The mockery is amusing but historically misleading, and I say so as one who has enjoyed it.
The addition of the iota changed the meaning substantially. ‘Same’ and ‘similar’ are not interchangeable when the question is whether the Son possesses the identical divine nature of the Father or merely resembles it. A contract for the same horse is not a contract for a similar horse, and nobody thinks lawyers absurd for knowing the difference. More importantly, the fourth-century controversy involved considerably more positions than these two words suggest. The word homoiousios was not even in play at Nicaea. It belongs to the 350s, a generation later, so that the popular picture of the bishops of 325 squabbling over an iota is wrong by about thirty years.
The so-called Homoiousians, associated with Basil of Ancyra and a council he held in 358, taught that the Son was like the Father according to substance. They were not straightforward Arians, and often stood much closer to Nicene theology than did more radical groups. Their language reflected concern that homoousios might destroy the genuine distinction between Father and Son. Athanasius, who was a better politician than his reputation for obstinacy suggests, recognised this. He wrote that men who accepted everything else in the Nicene faith and hesitated only at the word were to be treated as brothers who meant what he meant.
At the opposite end stood theologians such as Aetius and Eunomius, usually described as Anomoeans, who argued that the Son was unlike the Father in substance. The Father’s defining characteristic was to be unbegotten, while the Son was begotten, and what differed in definition differed in being. Eunomius is reported to have claimed that he knew the essence of God as well as God knew it himself, which is not a claim that Arius would have made. Between these positions emerged the Homoian formula, which avoided the terminology of ousia or substance altogether and declared the Son to be ‘like the Father according to the Scriptures’. A statement drawn up at Sirmium in 357 went so far as to forbid any mention of substance, on the ground that the word was not in Scripture and the matter was beyond human understanding. The attraction of such a formula to a government is obvious. Everyone could sign it, because it settled nothing. The apparently simple division between Arian and Nicene had thus broken into several theological programmes, each with its bishops and its creed.
Constantius II and the Homoian Ascendancy
Imperial policy counted for still more under Constantine’s sons. For some years the Empire was divided, and while Constans ruled the West the Nicene party had a protector. Constans was murdered in 350, and by 353 Constantius II was sole Emperor. He favoured theological settlements opposed to the uncompromising Nicene position associated with Athanasius, though calling Constantius an ‘Arian emperor’ conceals the complexity of his policy. What he wanted was agreement, and he was prepared to use force to get it. At councils in Arles and Milan the western bishops were made to condemn Athanasius, and Athanasius reports the Emperor as telling them that his will should be taken for a canon. The witness is hostile, but the conduct fits. Liberius of Rome was sent to Thrace until he gave way. Hosius of Cordoba, who had carried Constantine’s letter thirty years before and was now close to a hundred, was kept at Sirmium for a year until he put his name to the formula of 357.
Constantius supported attempts to find a formula capable of commanding broad episcopal agreement, and the Homoian position became especially influential. At the twin councils of Rimini and Seleucia in 359, followed by developments at Constantinople, a creed emerged describing the Son as ‘like the Father according to the Scriptures’ while avoiding the disputed language of substance. Some four hundred western bishops had gathered at Rimini, most of them Nicene, and they were kept there into the winter until they signed. The draft put before them was headed with the names of the consuls and the day of the month. Athanasius enjoyed himself over this, asking whether the Catholic faith had come into being on the twenty-second of May.
Jerome later produced the famous complaint that ‘the whole world groaned and was astonished to find itself Arian’, ingemuit totus orbis, et Arianum se esse miratus est. The remark is rhetorically brilliant but should not be mistaken for a neutral statistical description. Jerome was writing twenty years afterwards and making a case. The settlement imposed under Constantius was Homoian and not Arian in the original sense, and many of the bishops who accepted it did so under considerable political pressure, or because they regarded it as a compromise capable of restoring peace to the Church.
Nevertheless, by the end of Constantius’s reign in 361, the Nicene formula of 325 was far from possessing the uncontested authority it later acquired. What followed did nothing to settle matters. Julian, who had given up Christianity altogether, recalled the exiled bishops of every party. Ammianus says he did it knowing that no wild beasts are so dangerous to men as Christians are to one another. In the East, Valens returned to the Homoian policy of Constantius and kept to it for fourteen years.
The Cappadocians and the Clarification of Nicene Theology
One reason Nicene Christianity eventually succeeded was that its defenders developed a more precise vocabulary than had been available in 325. The most important contributors were the Cappadocian Fathers, writing in the later fourth century. These were Basil of Caesarea, his younger brother Gregory of Nyssa, and their friend Gregory of Nazianzus.
They helped establish a distinction between ousia, usually translated as essence or substance, and hypostasis, usually rendered as person or individual subsistence. God could therefore be confessed as one ousia in three hypostaseis: one divine essence existing as Father, Son and Holy Spirit. How much of a change this was can be seen from the creed of 325 itself, whose anathemas use the two words as if they meant the same thing. For the Latins the confusion was worse, since substantia is the literal equivalent of hypostasis but was their translation of ousia, so that a Greek who spoke of three hypostaseis sounded to a western bishop as if he were confessing three Gods. Much of the mutual suspicion between honest men in these years came from nothing more than this.
The formula addressed one of the principal fears of eastern opponents of Nicaea. Saying that Father and Son were homoousios need not mean that they were the same person. Their unity belonged to the divine nature. Their distinction belonged to their personal relations. The resulting theology was not the creed of 325 repeated more loudly. It was a development and clarification of what the Nicene formula could mean. This helps explain why some theologians and bishops who had earlier been suspicious of homoousios could eventually accept a theology that called itself Nicene. Basil himself had begun his career in the company of the Homoiousians.
The settlement was therefore achieved in part through intellectual convergence, and was more than the defeat of one party by another. This is the part of the story that a wholly cynical account cannot explain. Emperors can exile bishops, but they cannot make a formula satisfy men who have thought about it for thirty years.
The Holy Spirit
The controversy also expanded beyond the original question of Father and Son. The creed of Nicaea, after its long article on the Son, had said only ‘and in the Holy Spirit’. Once the full divinity of the Son had been defended, the status of the Spirit demanded a corresponding explanation.
Some Christians who accepted a high Christology remained unwilling to accord the Spirit the same divine status. These opponents were sometimes called Pneumatomachians, ‘fighters against the Spirit’, or Macedonians, after a bishop of Constantinople who had been deposed in 360. Basil of Caesarea’s On the Holy Spirit was one of the important contributions to this later phase of the debate. It is a careful book. Basil argues that the Spirit is to be given the same honour as the Father and the Son, but he nowhere states outright that the Spirit is God, and his friend Gregory of Nazianzus, who had no such caution, had to defend him for it.
The fully developed doctrine of the Trinity therefore emerged through a connected series of controversies and did not come from a single decision at Nicaea. By the end of the century, orthodox theology confessed one divine nature shared fully and eternally by Father, Son and Holy Spirit, while maintaining genuine personal distinction among the three.
Theodosius and Constantinople
The political situation changed decisively when Valens was killed fighting the Goths at Adrianople in 378. His successor in the East, from January 379, was Theodosius I, a Spanish general and a western Nicene. In 380 Theodosius issued the Edict of Thessalonica in his own name and those of Gratian and Valentinian II. It identified the imperial form of Christianity with the faith held by the bishops of Rome and Alexandria and with belief in the equal divinity of Father, Son and Holy Spirit. Everyone else was pronounced dementes vesanosque, demented and insane, and their meeting places were not to have the name of churches. When he reached Constantinople at the end of the year, he gave the Homoian bishop the choice of accepting Nicaea or leaving, and handed over the churches of the capital, which that party had held for forty years.
In 381 Theodosius summoned the council later known as the First Council of Constantinople. About a hundred and fifty bishops came, all of them eastern. It reaffirmed the Nicene theological settlement, condemned by name a list of rival positions that ran from the Eunomians at one extreme to the Sabellians at the other, and established what became the dominant Trinitarian orthodoxy of the imperial Church. It was not an edifying assembly. Its first president died. Its second, Gregory of Nazianzus, resigned in disgust and went home to Cappadocia, and was replaced as bishop of the capital by a senator who had not yet been baptised. Gregory wrote the next year that he made a point of avoiding every gathering of bishops, since he had never seen a synod come to a good end.
The familiar creed commonly called the Niceno-Constantinopolitan Creed is traditionally associated with this council. Its precise textual relationship to the council of 381 is more complicated than older accounts sometimes suggest, since it first appears clearly in the surviving record of the Council of Chalcedon in 451, where it was read out as the faith of the hundred and fifty fathers. Nevertheless, the theology represented by the creed belongs to the consolidation of Nicene Christianity associated with Constantinople and the later fourth century. Its description of the Holy Spirit as ‘the Lord and giver of life’, proceeding from the Father and worshipped and glorified together with the Father and the Son, reflects the broadening of the controversy beyond Arius’s original question. It also shows Basil’s caution. The Spirit is given equal worship, but the word homoousios is not applied to him.
Imperial Power and Theological Argument
The Arian controversy is often used to illustrate the dangers of combining Church and State, and there is considerable justification for doing so. Emperors summoned councils, banished bishops, recalled exiles, enforced ecclesiastical settlements and sometimes attempted to compel doctrinal conformity. Bishops in turn competed for imperial influence and sought secular enforcement of ecclesiastical judgements. Readers who know my opinion of the State will expect me to say that this is what happens whenever government takes a view on matters it is not fit to judge, and I do say it. Four years after the Council of Constantinople, a Spanish bishop named Priscillian was tried before a secular court at Trier and beheaded. The charge was sorcery, but the cause was heresy, and he is commonly reckoned the first Christian to be put to death at the instance of other Christians for his opinions. The road from Constantine’s order to burn the books of Arius had been a short one.
Yet it would be equally misleading to treat the theology as a disguise for imperial politics. Constantine did not invent homoousios as an administrative slogan, and Athanasius did not spend decades defending the divinity of the Son because control of Alexandria was politically useful. The participants endured exile, loss of office and considerable personal danger because they believed the theological questions to be real. A man who wants only power does not spend six years hiding among the monks of the Egyptian desert, writing treatises, when a signature would restore him to his church.
The interaction worked in both directions. Theology became political because Christianity was becoming embedded in the institutions of the Empire. Imperial politics became theological because emperors increasingly regarded the unity of the Church as part of their responsibility for public order and divine favour. An emperor who thought that God gave victory to rulers whose subjects worshipped him correctly had the same interest in orthodoxy that a modern government has in the money supply.
There was, however, an irony in imperial involvement. Constantine summoned Nicaea partly in the hope of establishing unity, but imperial intervention often intensified the conflict. Once doctrinal settlements carried political consequences, losing a theological argument might also mean losing a bishopric or being sent into exile. The stakes rose, and with them the reasons for intrigue. Every change of emperor could reopen questions supposedly settled by the previous reign, as happened under Constantius, under Julian, under Valens, and under Theodosius. The controversy thereby helped establish a pattern that would recur throughout Byzantine history, in the long quarrels that followed Chalcedon and again in the fight over images.
There is one more effect, and it is the one I find most interesting. It was in these years that bishops first told an emperor to mind his own business. Hosius, before he was broken, wrote to Constantius that God had given the Emperor the government of the Empire and had given the affairs of the Church to the bishops, and that neither should meddle with the other. Ambrose of Milan, refusing in 386 to hand over a basilica for the use of the Homoian court, put it more shortly: imperator enim intra ecclesiam, non supra ecclesiam est. The Emperor is within the Church and not above it. These were at first the protests of men on the losing side, who had welcomed imperial help when it was given to them. But the idea, once stated, did not go away. The claim that there is a sphere of life in which the ruler has no authority has had a long history in the West, and a good part of what we mean by liberty descends from it. I do not suggest that Ambrose was a liberal. I suggest that he and Hosius, for reasons of their own, said something from which better things could later be made.
Arian Christianity among the Goths
The defeat of anti-Nicene theology within the Roman imperial Church did not mean that it disappeared. One of the lasting consequences of the controversy was the spread of a non-Nicene form of Christianity among the Germanic peoples, above all the Goths.
The missionary bishop Ulfilas, or Wulfila, worked among the Goths during the fourth century and translated much of the Bible into Gothic, having first devised an alphabet to write it in. He is said to have left out the Books of Kings, on the ground that his people were warlike enough already and needed no encouragement. A copy of his Gospels, written in silver ink on purple vellum and probably made at Ravenna in the time of Theodoric, survives at Uppsala. Ulfilas had been consecrated in about 341 by Eusebius of Nicomedia, and his Christianity belonged broadly to the Homoian tradition dominant during part of the reign of Constantius II. It was not the original theology of Arius in every detail.
This distinction is important, because the Christianity later practised by Visigoths, Ostrogoths, Vandals and other Germanic kingdoms is conventionally called ‘Arian’ but was usually Homoian. These peoples adopted Christianity during a period when non-Nicene forms enjoyed substantial imperial patronage, and they kept the faith they had received after the Roman imperial Church moved decisively towards Nicene orthodoxy. It was among the oddities of the battle of Adrianople that the Emperor Valens was killed by barbarians who shared his creed and had received it from bishops of his own party.
The result was one of the more curious legacies of the controversy. During the fifth and sixth centuries, many of the Germanic rulers of former western Roman territories were ‘Arian’ Christians governing predominantly Nicene populations. The theological division therefore survived the fall of the western Empire and became entangled with distinctions of language, ethnicity and political identity. A Goth went to one church and a Roman to another. In Ravenna, where Theodoric ruled Italy, the Arian baptistery still stands a few streets from the Catholic one. Theodoric left his Catholic subjects alone. The Vandals in Africa did not, and their kings exiled and sometimes killed Nicene clergy. For the conquerors, a separate creed was a means of remaining a separate people. It was also a weakness, and the Franks under Clovis, who went directly from paganism to Catholic baptism, found that the Roman bishops of Gaul were on their side.
Over time these kingdoms generally converted to Nicene Christianity. The Visigothic kingdom of Spain formally abandoned Arianism at the Third Council of Toledo in 589, and the Lombards in Italy followed in the next century. By then the controversy had long ceased to threaten Nicene dominance within the former Roman world.
Was Arius Obviously a Heretic?
From the standpoint of later Nicene Christianity, Arius is straightforwardly a heretic because he denies the full eternal divinity of the Son. Historically, however, it is important not to write as though Arius had rejected a fully formulated doctrine of the Trinity already universally accepted by Christians. The standard modern history of the controversy, by Richard Hanson, is called The Search for the Christian Doctrine of God, and the first word of the title was chosen with care. Nobody in 318 was defending a settled doctrine. They were looking for one.
The terminology in which orthodoxy was eventually expressed was still developing when the controversy began. Arius drew on genuine strands of earlier Christian theology, including traditions that spoke of the Son as subordinate to the Father. Rowan Williams, in the best book on him, presents a conservative Alexandrian defending what he took to be the teaching of his predecessors. His opponents likewise drew on older traditions affirming the eternal and divine status of the Word.
What changed during the fourth century was partly the precision with which the alternatives were defined. Positions that had once existed beside one another with a degree of ambiguity became increasingly difficult to reconcile once theologians asked what words such as ‘begotten’, ‘divine’, ‘eternal’ and ‘Son’ implied about the being of God. The controversy therefore did not create belief in Christ’s divinity from nothing. Christians had worshipped Christ and described him in divine terms long before Nicaea, as Pliny found. What the controversy did was force the Church to define much more carefully what that language meant.
It may be added that the question has never stayed closed. Whenever educated men have read the New Testament for themselves and without the creeds beside them, some have come away with a view much like that of Arius. Milton did. So, in his private papers, did Isaac Newton, who regarded Athanasius as a forger and a scoundrel and took care to keep the opinion to himself. His successor in the Lucasian chair at Cambridge, William Whiston, was less careful and was deprived of it in 1710. The Jehovah’s Witnesses hold something close to the same doctrine today. This does not show that Arius was right. It shows that his reading of the texts was a natural one, and that the Nicene reading needed arguing for.
Nicaea and the Development of Doctrine
This raises the larger question of doctrinal development. The Nicene Creed contains terminology that does not occur in the New Testament. Neither homoousios nor the later formula ‘one essence in three persons’ is a biblical phrase.
To some readers this can look like evidence that the fourth-century Church replaced the simpler faith of the New Testament with Greek metaphysics. The great name here is Adolf von Harnack, who taught more than a century ago that dogma was the work of the Greek spirit on the soil of the Gospel. There is a serious historical question behind the criticism, since fourth-century theologians unquestionably used the conceptual resources of Greek philosophy.
But the opposite conclusion is also possible. Technical vocabulary became necessary because biblical vocabulary could be interpreted in incompatible ways. Arius could call Jesus ‘Son of God’, ‘divine’ and ‘begotten’ while understanding these expressions very differently from Alexander or Athanasius. Repeating scriptural words did not settle the disagreement, because both sides were happy to repeat them. Any lawyer will recognise the position. The general words of a statute do well enough until two parties read them in opposite senses, and then a court must say in words of its own which sense is meant.
The purpose of homoousios was therefore to specify what one interpretation of Scripture excluded, and those who introduced it did not think they were putting philosophy in the place of Scripture. The Son could not be called divine while being placed ultimately within the created order. The non-biblical term was introduced to control the meaning assigned to biblical language. This was the argument of Athanasius at the time, and it was Newman’s argument fifteen hundred years later, when he wrote his history of the Arians and then his essay on development.
Whether this development should be regarded as faithful clarification or as theological innovation is partly a confessional judgement, and I do not offer one. Historically, however, the process is clear enough. Controversy forced increasingly exact definitions.
The Lasting Importance of the Controversy
The immediate theological result of the Arian controversy was the consolidation of Nicene Trinitarian Christianity. The Son was confessed as eternal, uncreated and fully divine, sharing the one divine essence with the Father while remaining personally distinct from him. The Holy Spirit was subsequently brought into the same Trinitarian structure. This theology became normative for the churches that developed into Eastern Orthodoxy, Roman Catholicism and the major traditions of Protestant Christianity. The creed recited every Sunday in an English parish church is, with one notable western addition, the creed read out at Chalcedon.
Its institutional effects were almost as important. Nicaea strengthened the idea that disputes affecting the whole Church could be addressed by assemblies of bishops whose decisions claimed universal authority. The later category of the ‘ecumenical council’ developed from this experience, although the exact authority of councils, and the criteria by which a council was to be accepted as ecumenical, remained subjects of later dispute. Rimini had been larger than Nicaea and had the Emperor’s approval, and it is not on anyone’s list.
The controversy also transformed relations between Emperor and Church. Constantine’s intervention had at first seemed capable of settling an ecclesiastical quarrel. What it did was to establish a precedent by which emperors became deeply involved in doctrinal affairs. Bishops discovered both the usefulness and the danger of imperial support. Athanasius could benefit from one emperor and be expelled by another, and theological parties could move rapidly from triumph to disgrace as the political situation changed.
There is consequently no simple story in which the State imposed Nicene Christianity on an unwilling Church. For most of the half-century between Nicaea and Constantinople, imperial authority in the East favoured positions hostile to the Nicene party. Nicene theology survived those periods partly because its supporters had intellectual, ecclesiastical and popular bases independent of the court. There were the monks of Egypt, who hid Athanasius and could not be bribed. There were the Latin churches, which never wavered for long. When Theodosius eventually used imperial power in support of Nicene Christianity, he strengthened a theological movement that had already spent decades developing its arguments and alliances. He gave the victory its legal form. He did not create it.
Conclusion
The Arian controversy began with a dispute in Alexandria over a question that can be stated simply but proved extraordinarily difficult to answer. In what sense is Jesus Christ the Son of God?
Arius attempted to preserve the absolute uniqueness of God the Father by insisting that the Son derived his existence from the Father’s will. Christ was pre-existent, heavenly and incomparably greater than ordinary creatures, but he was not eternal in the same sense as the Father and did not possess the same underived divine being. For Alexander, Athanasius and the theologians who eventually prevailed, this distinction made the Son a creature, however exalted, and therefore undermined both Christian worship of Christ and the belief that in Christ humanity encountered God himself.
Nicaea answered Arius in 325 by declaring the Son homoousios with the Father, but that formula did not end the argument. It generated further questions about what common substance meant and how unity of essence could coexist with personal distinction. The following half-century saw repeated councils, exiles and imperial interventions, and the emergence of Homoian, Homoiousian and Anomoean alternatives beside a developing Nicene theology.
The eventual victory of Nicaea was therefore not simply the enforcement of one decision taken in 325. It depended on decades of theological clarification, particularly the distinction between one divine essence and three persons developed by the Cappadocian Fathers. By the Council of Constantinople in 381 the broad structure of the doctrine later recognised as orthodox Trinitarian Christianity had emerged.
The controversy also reveals something important about the development of Christian doctrine more generally. The fourth-century Church did not begin with a complete technical doctrine of the Trinity and then discover that Arius had inexplicably rejected it. Nor did Constantine gather a group of bishops and invent the divinity of Christ by imperial decree. Christians had been worshipping Christ, reading Scripture and arguing about his relation to God for centuries. What Arius did was force questions that could no longer be answered by deliberately ambiguous language.
Once Christians asked whether the Son was eternal or created, whether his divinity was intrinsic or bestowed, and whether worship offered to him was worship of God or of the highest creature, compromise became increasingly difficult. The answer eventually given at Nicaea and developed during the following generations was that the Son belongs wholly to the divine side of the distinction between Creator and creation. That conclusion has remained one of the defining propositions of historic Christianity ever since.
I began with Gibbon, and I will end with him. He was right that the spectacle is often absurd, and no one who reads the sources can miss the vanity and the bullying, or the readiness of holy men to call in the police. I still think the bath attendant funny. But the question was a real one, the difference between the answers was a real difference, and the men who fought over it were not fools. A city in which the bakers and the money changers have opinions on the generation of the Son is at least a city that thinks some questions worth getting right. I am less sure than I was that the laugh is on them.