Chalcedonian Definition

The Council of Chalcedon in 451 was called by the emperor Marcian, with the empress Pulcheria behind it, to settle how the divine and the human are joined in Christ. Two answers had been condemned already and the council had to exclude both without falling into either. Nestorius had been read as dividing Christ into two subjects. Eutyches, an archimandrite of Constantinople, taught that after the union there was one nature, the human absorbed into the divine.

The definition answers with a formula of great precision. Christ is confessed in two natures, divine and human, made known without confusion, without change, without division, without separation. The first two adverbs exclude Eutyches, refusing any mixing or alteration of the natures. The second two exclude the division ascribed to Nestorius. The natures are not fused and they are not separable, and both are affirmed in one person and one hypostasis.

The council did not invent this from nothing. It quoted the creeds of Nicaea and Constantinople in full, endorsed the letters of Cyril of Alexandria, and read the Tome of Leo, the letter of the Roman bishop that supplied much of the Western phrasing. The definition presents itself as clarification of an existing faith rather than as new doctrine, which is the standard conciliar posture and is also, in this case, a claim that a large part of the church refused to accept.

Chalcedon settled Christology for the churches that received it and split the church for those that did not. The bishops of Egypt, of much of Syria and later of Armenia and Ethiopia held that the definition's language of two natures conceded too much to Nestorius and betrayed Cyril of Alexandria, whose formula of one incarnate nature of the Word they regarded as the standard of orthodoxy. The churches descending from that refusal are the Oriental Orthodox, and their separate existence dates from this council.

Calling that position monophysite, which older Western writing routinely did, misstates it. Eutyches taught that the humanity was swallowed by the divinity, and the Oriental Orthodox condemned him too. Their position, generally called miaphysite, holds one united nature in which the divine and the human remain complete and unmixed. The distinction is not a technicality: the whole dispute is about whether that formula and the Chalcedonian one describe the same faith in different vocabularies.

Modern dialogue has moved a long way on precisely that question. Bilateral agreed statements between Oriental Orthodox and both Eastern Orthodox and Catholic churches have declared that the parties confess the same faith in Christ, while the canonical separation continues and the anathemas of 451 remain part of the record. Fifteen hundred years of divergent liturgy, hierarchy and law are not undone by agreeing about a formula, which is itself a fact worth knowing about how churches divide.