Monophysitism / Miaphysitism
μία φύσις — mia physis · MEE-ah FEE-sis
In brief
Monophysitism ("one-nature-ism") is the condemned teaching of Eutyches that Christ's humanity was swallowed up in His divinity, so that He is not truly one of us. Miaphysitism is something different: the confession of the Oriental Orthodox churches — appealing to St. Cyril's formula — that Christ is fully God and fully man in one united incarnate nature, without confusion or change. The Fourth Ecumenical Council at Chalcedon (451) condemned Eutyches and confessed one Christ "in two natures" — and over that wording came a lasting division — the oldest still separating whole families of churches within the empire's heirs, one that modern dialogue gives real hope of healing.
Eutyches: the pendulum swings back
After the Council of Ephesus struck down the division of Christ into two subjects, the opposite temptation appeared. Eutyches, an elderly and influential archimandrite in Constantinople, defended the unity of Christ so fiercely that His humanity began to vanish: Eutyches would speak of two natures before the union but only one after it, and he balked at confessing that Christ's flesh is of one essence with ours. However pious the motive, the result is fatal to the Gospel. If the Lord's humanity is dissolved into divinity, He is no longer truly one of us — and Scripture insists that "in all things it behoved him to be made like unto his brethren" (Hebrews 2:17), for only what He truly shares with us can He heal.
Eutyches was condemned by a synod at Constantinople in 448. The next year a council at Ephesus (449), dominated by his allies, reinstated him and deposed his judges — a gathering so coerced that Pope St. Leo the Great branded it a latrocinium, an act of brigandage, and history remembers it as the "Robber Council."
Chalcedon, 451
The Fourth Ecumenical Council met at Chalcedon in 451. Drawing on St. Cyril's letters and St. Leo's Tome, it condemned both Nestorius and Eutyches and confessed one and the same Christ, perfect in Godhead and perfect in manhood, made known "in two natures, unconfusedly, immutably, indivisibly, inseparably" — two natures, never two Sons, united in one Person.
But the settlement did not settle everything, because the key word — physis, "nature" — was heard differently in different places. For many heirs of Cyril in Egypt and Syria, physis meant a concrete living reality, close to what Chalcedon meant by "person"; to their ears, "in two natures" sounded like two Christs — Nestorianism returned under seal. They held instead to Cyril's own formula, "one incarnate nature of God the Word" (mia physis tou Theou Logou sesarkomene) — a phrase Cyril had received as St. Athanasius's, though scholars now trace it to Apollinarian sources. The deposition of Dioscorus, Archbishop of Alexandria, deepened the wound; his heirs note that he was deposed for his conduct concerning the council, not by any formal finding of heresy. Large parts of Egypt, Syria, and Armenia never received Chalcedon, and the first great and lasting division within the imperial Church followed.
Monophysite or miaphysite?
The churches that could not accept Chalcedon are today's Oriental Orthodox family: the Coptic, Armenian Apostolic, Syriac, Ethiopian, Eritrean, and Malankara (Indian) churches. And here a distinction is essential, because it is a matter of simple fairness: they do not teach, and have never taught, what Eutyches taught. They condemn Eutyches as firmly as Chalcedon did. Following Cyril — and their great theologian Severus of Antioch — they confess Christ perfect in His divinity and perfect in His humanity, one united divine-human nature without mingling, without confusion, without alteration.
For this reason they describe their position as miaphysite — from mia, "one" in the sense of one united reality — and regard "monophysite," which properly describes Eutyches's absorbed-humanity Christology, as a misnomer when applied to them. The real question their existence poses is whether fifteen centuries of separation rest on two different faiths or on two vocabularies for the same faith.
The modern dialogue
In the twentieth century the two families finally examined that question together. The official Joint Commission produced two landmark texts: the First Agreed Statement at the Monastery of St. Bishoy in Egypt (1989) and the Second Agreed Statement at Chambésy, Switzerland (1990). The second statement's conclusion was remarkable: that "both families have always loyally maintained the same authentic Orthodox Christological faith," expressed in different terms; that "both families agree in condemning the Eutychian heresy"; and that the ancient anathemas — pronounced, it now appeared, against positions the other family does not actually hold — "should be lifted by the Churches."
These statements are the work of a commission, not yet the act of the Church: they await formal reception, some Orthodox voices — including on Mount Athos — have raised serious objections concerning the councils and figures such as Severus, and communion has not been restored. Orthodox Christians are not required to prejudge what the Church has not yet decided. What is undisputed is this: both families confess one Lord Jesus Christ, fully God and fully man; both reject Nestorius and Eutyches by name; and both have reason to pray, with more hope than at any time in fifteen hundred years, for the healing of this ancient wound.