Eutyches of Constantinople, an early heretic of the 5th century, at various times, taught that the human nature of Christ was overcome by the divine, or that Christ had a human nature but it was unlike the rest of humanity. His developed doctrine is called Eutychianism.
Eutychianism refers to a set of Christian theological doctrines, derived from the ideas of Eutyches of Constantinople (c. 380 – c. 456), which were condemned at the Ecumenical Council of Chalcedon in 451. Eutychianism is a specific Christology having a particular understanding of how the human and the divine are related within the one person of Jesus Christ, an understanding rejected by the Catholic and Orthodox Churches, and major denominations of Protestantism, Lutheran, Presbyterian, Methodist, Baptist, Congregationalist.
One formulation of the doctrine of Eutychianism stresses the unity of Christ's nature to such an extent that Christ's divinity consumed his humanity as the ocean consumes a drop of vinegar. Eutyches maintained that Christ was of two natures in his Incarnation, but not one in two natures in himself. Although more senior bishops and theologians sought to correct him, he insisted that the separate divine and human natures had been so united and blended in such a manner that although Jesus was homoousian, one essence of being with the Father, he was not homoousian with man. Thus, God the Son was crucified in his divinity, but not in his humanity, which was totally united with his divinity in one nature.
Eutychianism is opposed to the doctrine of Nestorianism, which denies that the one Person of the Son of God has two natures, both divine and human. Nestorianism fundamentally differentiates and separates the Divine Person of the Son of the Father, the Logos, having a divine nature only, from the human person of Jesus Christ, having a human nature only, such that while different in both nature and being, they so perfectly cooperated that they were virtually one in activity, but not actually one in being. Thus God the Son was not crucified, but the human Jesus was crucified, being in perfect submission to the will of God perfectly manifested through him, as if the Word had virtually become flesh in him. Thus, God raised Jesus from the dead by his power through His Word, through the Son of God. Arguments between the opposing factions of the Eutychians and the Nestorians became so extreme that violent riots often broke out between them.