Eutychian heresy

Eutyches (Greek: Εὐτυχής; c. 380 – c. 456) was a presbyter and archimandrite at Constantinople. He first came to notice in 431 at the First Council of Ephesus, for his vehement opposition to the teachings of Nestorius; his condemnation of Nestorianism as heresy led him to an equally extreme, although opposite view, which precipitated his being denounced as a heretic himself.

Eutyches was an archimandrite of a monastery outside the walls of Constantinople, where he ruled over three hundred monks. He was much respected and was godfather to Chrysaphius, an influential eunuch at the court of Theodosius II.

The Archbishop of Constantinople, Nestorius, having asserted that Mary ought not to be referred to as the "Mother of God" (Theotokos in Greek, literally "God-bearer"), was denounced as a heretic; in combating this assertion of Patriarch Nestorius, Eutyches declared that Christ was "a fusion of human and divine elements", causing his own denunciation as a heretic twenty years after the First Council of Ephesus at the 451 AD Council of Chalcedon.

According to Nestorius, all the human experiences and attributes of Christ are to be assigned to 'the man', as a distinct personal subject from God the Word, though united to God the Word from the moment of his conception. In opposition to this, Eutyches inverted the assertion to the opposite extreme, asserting that human nature and divine nature were combined into the single nature of Christ without any alteration, absorption or confusion: that of the incarnate Word. Although this accorded with the later teaching of Cyril of Alexandria, Eutyches went beyond Cyril in denying that Christ was 'consubstantial with us men', by which he did not intend to deny Christ's full manhood, but to stress His uniqueness.

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