The Council of Ephesus

In April 428 Nestorius, a preacher from Antioch, was made bishop of Constantinople (Socrates, Church History 7.29). One of his presbyters preached that Mary should not be called Theotokos, “God-bearer”, because God cannot be born of a woman, and Nestorius defended him. The historian Socrates, who read his sermons, concluded that Nestorius did not deny that Christ is God but was frightened by a word (Socrates, Church History 7.32).

Cyril of Alexandria wrote to correct him. The Word of God, he says, “having personally united to himself flesh animated by a rational soul”, became man; the natures remain distinct, but “the two natures being brought together in a true union, there is of both one Christ and one Son”. Because the body that was born and suffered was the Word’s own, the Word himself is said to have been born and to have suffered, and the fathers rightly called the Virgin Mother of God (Council of Ephesus (431) Cyril, second letter to Nestorius).

Nestorius replied that the creed first names the Lord Jesus Christ, titles common to the godhead and the manhood, and only then speaks of birth and suffering. Scripture, he wrote, assigns these to Christ’s humanity and never to the godhead, so that Mary is more exactly called mother of Christ than mother of God. The body is the temple of the deity; to make the divine Word himself the subject of birth and death is the error of Apollinarius and Arius (Council of Ephesus (431) Nestorius, second letter to Cyril).

The emperor Theodosius II summoned the bishops to Ephesus. Cyril and his supporters opened the council before John of Antioch and the Syrian bishops had arrived. Nestorius refused to appear and was deposed “with many tears” (Socrates, Church History 7.34) (Council of Ephesus (431) decree against Nestorius). The legates of the bishop of Rome came later and confirmed the sentence (Council of Ephesus (431) session 3). Nestorius’s supporters, joined by John, declared Cyril deposed in turn, but the sentence against Nestorius stood and he was exiled (Socrates, Church History 7.34).

In 433 Cyril and John made peace on a statement that Christ is perfect God and perfect man, of one substance with the Father in his divinity and with us in his humanity, “for there became a union of two natures”, and that the Virgin is therefore Mother of God (Council of Ephesus (431) Cyril to John of Antioch (433)). The Council of Chalcedon in 451 received Cyril’s synodical letters to Nestorius and to the eastern bishops (Definition of Chalcedon).

The church of the Persian empire, with its own catholicos and synods (see the Church of the East Organises at Seleucia-Ctesiphon), lay beyond the Roman frontier. Its descendant, the Assyrian Church of the East, prays to Mary as the Mother of Christ, our God and Saviour (Common Christological Declaration (1994)). In 1994 its Catholicos-Patriarch and the pope confessed a common faith in Christ, recognised that title and Mother of God as legitimate expressions of it, and said that the divisions which followed the old controversies and anathemas were due in large part to misunderstandings (Common Christological Declaration (1994)). The joint commission of the two churches wrote in 2017 that this ended an age-old controversy over the Christological implications and consequences of the Council of Ephesus (Catholic–Assyrian Common Statement on Sacramental Life (2017) introduction).