Condemned Arius and confessed the Son consubstantial with the Father, giving the Church its first common Creed and a rule for dating Easter.
- Where
- Nicaea in Bithynia — İznik, Turkey
- Convoked by
- The emperor Constantine, who wrote personally to the bishops of every province and put the imperial post at their disposal
- Pope
- Sylvester I, who did not attend; he was represented by two priests, Vitus and Vincentius
- Emperor
- Constantine I, present in person at the opening
- Sat
- Opened 19 June 325; the sessions ended on 25 August
- Sessions
- Held in the imperial palace at Nicaea. The acts have not survived; what we have are the creed, the canons and the letters
- Bishops present
- The traditional figure is 318 — a number chosen to echo Abraham's 318 servants in Genesis 14. Contemporary and near-contemporary counts run from about 250 to 'more than 300'
What it faced
Arius was a priest of Alexandria, an ascetic and a popular preacher, and his argument was not stupid. If the Son is begotten, he reasoned, then there was a beginning to his being begotten; and if there was a beginning, then there was — as his slogan ran — a time when he was not. The Son would then be the first and greatest of all creatures, made before time and through whom everything else was made, but a creature nonetheless. Arius thought he was defending the one God against a rival.
His bishop, Alexander of Alexandria, excommunicated him around 318, and the quarrel spread through the eastern Church faster than any authority could contain it. Constantine, who had ended the persecutions barely a decade earlier and wanted an empire at peace, found his new religion tearing itself apart over a Greek preposition. He summoned every bishop in the world to Bithynia at his own expense.
The question underneath was not academic and the bishops knew it. If the Son is a creature, then a creature is worshipped at every Christian altar, and what the martyrs had just died refusing to do — bow to a creature — the Church was doing every Sunday. If the Son is God, then whatever else is true, the God who made the world came into it himself.
What it defined
- ✠That the Son is begotten, not made — generated from the Father's own being, not produced out of nothing like everything else.
- ✠That he is homoousios with the Father: of the same substance, the same being. Not merely similar, not merely divine in a lesser degree.
- ✠That the propositions of Arius — 'there once was when he was not', 'before he was begotten he was not', 'he came to be from things that were not' — are anathema.
- ✠A common rule for calculating Easter, so that the whole Church would keep the Pasch on the same Sunday.
- ✠Twenty canons of discipline, including the standing of the great sees and the prohibition of clerical usury.
In its own words
“We believe in one God the Father all powerful, maker of all things both seen and unseen. And in one Lord Jesus Christ, the Son of God, the only-begotten begotten from the Father, that is from the substance of the Father, God from God, light from light, true God from true God, begotten not made, consubstantial with the Father…”
“And those who say 'there once was when he was not', and 'before he was begotten he was not', and that he came to be from things that were not… these the catholic and apostolic church anathematises.”
“The ancient customs of Egypt, Libya and Pentapolis shall be maintained, according to which the bishop of Alexandria has authority over all these places, since a similar custom exists with reference to the bishop of Rome. Similarly in Antioch and the other provinces the prerogatives of the churches are to be preserved.”
Its canons
The disciplinary rules it made — law, not doctrine, and most of them long since changed.
- Canon 5A provincial synod must be held twice a year, and excommunications may be reviewed there — the beginning of appeal in Church law.
- Canon 6Alexandria, Rome and Antioch keep their ancient prerogatives over their regions.
- Canon 7The bishop of Aelia — Jerusalem — is to be honoured according to ancient tradition, without prejudice to his metropolitan.
- Canon 8Novatianist clergy returning to the Church are received by the laying on of hands, not re-ordained.
- Canon 17Clergy who lend at interest are to be deposed — the root of the Church's long war on usury.
- Canon 20On Sundays and through the fifty days of Eastertide, prayer is made standing, never kneeling: one may not kneel in the season of the Resurrection.
- ✕It did not decide the canon of Scripture. The subject never came before it. No list of books was drawn up, no gospels were voted out, and the four-gospel canon was already settled in practice a century and a half earlier.
- ✕It did not invent the divinity of Christ. Both sides at Nicaea worshipped Christ and had done so for as long as there had been Christians. The argument was about how he is divine, not whether.
- ✕It did not decide by a narrow vote. All but two of the bishops present subscribed. Three others had objected to homoousios and then signed.
- ✕It did not fix the date of Christmas, nor say anything about the soul of Mary, nor establish the papacy — its sixth canon is a statement of existing custom in Egypt, Rome and Antioch, not a grant of new authority.
- ✕It did not end Arianism. For the next fifty years the Arians generally had the emperors, and the bishops who held to Nicaea were the ones going into exile.
What people think it did
Constantine convened Nicaea to make Jesus into God, and the bishops voted on his divinity in a close ballot that could easily have gone the other way.
What happened: This is the version popularised by The Da Vinci Code, and it inverts the history. Christians had worshipped Christ as divine since the first century — Pliny reports it to Trajan around 112, describing Christians singing 'a hymn to Christ as to a god'. Arius himself held the Son to be a supernatural being existing before all ages; nobody at Nicaea was proposing a merely human Jesus. And the outcome was not close: all but two of the bishops signed.
Nicaea chose which gospels went into the Bible and suppressed the others.
What happened: The canon was not on the agenda and is not mentioned in the creed, the canons, or any contemporary account of the council. Irenaeus was already arguing for exactly four gospels around 180, and the Muratorian fragment lists most of the New Testament earlier still. The canon was settled by usage and by later local councils — Rome in 382, Hippo in 393, Carthage in 397.
St. Nicholas punched Arius at the council.
What happened: A charming story with no early evidence. It appears more than a thousand years after the event, and Nicholas of Myra's presence at Nicaea is itself not attested in any early list. The Church has never taught it, and it is repeated here only because it circulates every December.
What followed
Nicaea did not settle anything for two generations. Constantine himself was baptised on his deathbed by an Arian bishop; his son Constantius II backed the Arians outright; and Athanasius of Alexandria, who had come to Nicaea as a young deacon, spent seventeen of his forty-five years as bishop in exile for refusing to yield the word homoousios. Jerome's line about the period is the one everyone quotes: the world groaned and was astonished to find itself Arian.
What finally carried it was not imperial power but the Cappadocian fathers — Basil, Gregory of Nazianzus, Gregory of Nyssa — who spent the middle of the century showing that the Nicene word could be said without collapsing the three persons into one. The Council of Constantinople in 381 ratified their work and gave the creed the form still said at Mass.
The Easter rule had a longer life than the controversy. It is why the whole Church keeps Easter on a Sunday, and — because East and West later diverged over the calendar rather than the rule — why the dates still part most years.
Follow it further
Sources
- First Council of Nicaea — creed, canons and letters (English)
- Catholic Encyclopedia: The First Council of Nicaea
Every date, figure and quotation on this page was checked against the conciliar text or a published translation before it was written, and independently re-checked by three separate passes over dates, quotations and theology. Where the sources disagree — attendance figures above all — the page gives the range rather than choosing.