EUTYCHES, filti-kez ( Lat., from Gk. Ebr6x775). A monk of the fifth century, archimandrite of a cloister near Constantinople, who in his old age taught views respecting the nature of Christ which were condemned as heretical. He pos sessed little education, but was fond of doc trinal controversy. in which the whole Church at that time was engaged. His peduliar teaching was a development of the Alexandrian Chris tology. He held that two natures, one divine and one human, went to make up the person of Christ, but that after their union in the incarnation there was only one nature. He was unwilling even to admit that Christ's physical body was like that of ordinary men. Thus his theory tended to dissolve the true humanity in the divinity of Christ.
At a synod held at Constantinople in 443, under Flavian, Bishop of Constantinople, Eu tyches was charged with heresy by Eusebius of Poryl:rum, and condemned. Under Alexandrian influence the Emperor was persuaded to summon a council which should review the ease of Eu tyches. This council met. at Ephesus in 449. and is known as 'The Robber Synod,' from the riotous character of its proceedings. (See EPHESUS, COUNCILS OF.) By the aid of armed soldiers and
excited monks, Flavian was condemned and Eu tyches rehabilitated. But the Church at large properly refused to recognize as final the verdict of this disgraceful assembly, and a change in emperors made its reversal politically possible. Under Puleheria and Marcia!' the fourth ecu menical council was held at Chalcedon (451), arid there the doctrine of the two natures in Christ was declared to be an artiele of the Catholic faith. Entychianism was again con demned, and Eutyches himself, now seventy-three years old, was excommunica t ed and banished. We hear of him for the last, time two years later, when he was still in exile. His followers eon tinned their separate existence for a time, having monasteries of their own, but were soon lost sight of among the Alonophysites (q.v.), who composed a large majority of the Eastern Church. See LE() I., and consult: Hefele, His tory of the Councils, iii. (Eng. trans., London, 1883 ) ; Ha mina, History of Dogma, vol. iv. (Eng. trans., London, 1898) ; Du Bose, The Ecumenical Councils (New York, 1897).