Definition of Chalcedon
451. The majority at the * acknowledged the , confirmed at Constantinople, together with two Cyrilline letters and the . Alarmed by reluctant Egyptian bishops and recalcitrant supporters of the condemned Eutyches, the imperial commissioners pressed for a new unifying formula. A committee headed by Anatolius of Constantinople produced a draft containing the Cyrilline “out of two natures.” Others preferred the Leonine “in two natures,” and the commissioners reconstituted the committee. This produced the extant Definitio. Basically it affirms, first, that the Lord Christ is one, His two natures preserved in one prosopon and hypostasis. This favored the Alexandrine stress on One God. Second, it states that both natures, God and man, are unimpaired, “perfect,” consubstantial with God and man, preexistent and born of the Virgin. He is “acknowledged in two natures” (a phrase perhaps taken from ) “unconfusedly, unchangeably, indivisibly and inseparably.” The commissioners had commended this last Leonine phrase. Third, the Definition affirmed that the distinct natures are fully God and man, thus securing salvation by a saving God and a man identified with men. Confirmed by Emperor Marcian and Pulcheria, the Definition has split the Monophysite* from other Eastern churches.
T.H. Bindley and F.W. Green, The Oecumenical Documents of the Faith (1950 ed.); A. Grillmeier, Christ in Christian Tradition (ET 1965); R.V. Sellars, The Council of Chalcedon (1953).