Ephesus and Chalcedon

Nicaea had established that Christ is truly God. There remained a question just as formidable: if he is God, how is he also man, and how do these two realities hold together in a single being? Two councils answered it, at Ephesus in 431 and at Chalcedon in 451. From their work came the faith the Church has confessed ever since: one single Christ, true God and true man.

Nestorius and the Title of Mary

The debate broke out around a word the Christian people gave to the Virgin: Mother of God. Nestorius, patriarch of Constantinople, refused it; he would call Mary only Mother of Christ, judging it impossible that a woman should have brought God into the world. Behind the title lay a far graver question. By thus separating the divine and the human, Nestorius came close to making of Christ almost two beings set side by side: on one side God the Word, on the other the man Jesus, joined by a mere agreement. But if the one who is born of Mary, suffers and dies is not God himself, but a man indwelt by God, then it is not God who saved us, and the bond between God and man comes undone.

The Council of Ephesus

In 431, the council gathered at Ephesus, led by Cyril of Alexandria, decided against Nestorius. It confessed that there is in Christ only one single person, the Son of God, who is at once God and man. He is not a man united to God, but God himself who, without ceasing to be God, became man. From then on the title of Mary followed of itself: since the one she carried and bore is a single person, and this person is God, Mary is truly Mother of God. Not that she gives the divinity its origin, which would be absurd, but because the one she brought into the world according to his humanity is, in person, the Son of God: she is truly the Mother of God. The people of Ephesus, devoted to the Virgin, welcomed the news with joy.

Ephesus did not, however, at once bring peace. Cyril of Alexandria and the bishops of Syria, led by John of Antioch, remained divided for two years: the first feared that Christ would be split apart, the second that his two natures would be blurred together. In 433, an accord called the Formula of Reunion reconciled them: John of Antioch acknowledged Mary as Mother of God, and Cyril accepted that two natures, united without confusion, be distinguished in Christ. So, even before Chalcedon, the Church already held the two words that would guard the mystery: one single person, two natures.

The Opposite Excess

The condemnation of Nestorius soon provoked the contrary error. A monk of Constantinople, Eutyches, wished so strongly to unite the divine and the human that he ended by confusing them: according to him, the humanity of Christ had been as it were absorbed into his divinity, like a drop of water in the sea, so that there remained in him only one nature, the divine. This doctrine, which will be called monophysitism, from the Greek for “one single nature,” destroyed salvation from the other end. For if Christ is not fully man, he did not truly take our humanity, and what he did not assume, he did not heal. To save us, he had to be entirely God and entirely man.

Eutyches’s error was not set aside without drama. Condemned in 448 by Flavian, bishop of Constantinople, he gained his revenge the next year: a council gathered again at Ephesus in 449, held by force under Dioscorus of Alexandria, restored him, deposed Flavian, who died of the blows he received, and refused even to read the letter in which pope Leo set forth the faith. Leo called that assembly a robbery. It took the death of the emperor Theodosius II, who had backed it, and the accession of Marcian for a free council to be summoned at last. So Chalcedon gathered, to judge what that show of force had imposed.

The Council of Chalcedon

In 451 there gathered at Chalcedon the greatest council of antiquity. It relied on a letter of pope Leo, which set forth the faith with decisive clarity, and fixed the formula that has kept the mystery of Christ ever since: one and the same Christ, Son and Lord, acknowledged in two natures, without confusion, without change, without division, without separation. The union of the two natures does not mix them and does not suppress them: each keeps what is proper to it, the divine remaining fully divine and the human fully human, and both meet in one single person, that of the Son of God. So the Church holds both edges at once, against Nestorius who divided and against Eutyches who confused: one single person, two natures, true God and true man, the whole mystery of the Incarnation.

The Rupture and the Legacy

Chalcedon was not received everywhere. Whole Churches, above all in Egypt, in Syria and in Armenia, refused its formula, attached to confessing in Christ only one nature; they then separated from the Church, and that separation lasts still. But for the Church, the formula of Chalcedon has become the foundation of all she says of Christ. That the Son of God truly took flesh, that he truly suffered, that Mary is Mother of God, that his cross saves us: all rests on this truth held in one piece. As at Nicaea, the Church had added nothing to her faith; she had found the words to keep it intact against those who, each from one side, were breaking it.

These Churches, today called Oriental Orthodox, are above all those of Egypt (the Copts), of Syria and of Armenia, later joined by Ethiopia. Their refusal was not that of Eutyches: they did not confuse the natures, but held to Cyril’s formula, “one incarnate nature of the Word,” from which comes the name miaphysite given to them. This was the first great lasting division of Christendom, six centuries before that of East and West. The dialogue of recent times has recognized that the faith was often the same under different words: one single Christ, true God and true man.