Synaxis Holy Fathers of the First Ecumenical Council

The First Ecumenical Council was convened by St Constantine the Great in 325 at Nicaea in Bithynia. Its occasion was the teaching of the Alexandrian presbyter Arius, who held that the Son of God was created by the Father and not of one essence with Him.

Bishops gathered by 20 May 325; the emperor formally opened the sessions on 14 June in the great hall of the imperial palace, and the Council closed on 25 August. Ancient sources give from about 250 to over 320 participants; the traditional number of 318 Fathers goes back to St Hilary of Poitiers and St Basil the Great. Most bishops came from the eastern provinces, among them many confessors of the recent persecutions; by Church tradition St Nicholas of Myra and St Spyridon of Trimythous took part, and the deacon Athanasius, later St Athanasius the Great, accompanied Bishop Alexander of Alexandria.

The Council condemned Arianism and adopted the Creed confessing the Son as consubstantial with the Father, decided on the date of Pascha and issued twenty canons on church order. The Holy Fathers of the First Ecumenical Council are commemorated on the Seventh Sunday of Pascha; the Russian calendar also marks the memory of the Council on 29 May (11 June).