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Cyclopedia of Biblical, Theological and Ecclesiastical Literature [1]

a city of Bithynia. It was the seat of one of the so-called General Councils of the Church, held A.D. 451 (the fourth oecumenical council), which I was called by the emperor Marcianus, at the request of the bishops (especially of Leo I), to put down the Eutychian and Nestorian heresies. The emperor had first summoned the bishops to meet at Nicaea, but when the time approached he was prevented by political troubles from going so far from the imperial city, and therefore changed the place of meeting to Chalcedon, in Bithynia, on the Bosphorus, opposite Constantinople. The Council was attended by 630 bishops and deputies, all Eastern except four legates sent by Leo I from Rome. The sessions began Oct. 8, 451, and ended Oct. 31. As the two parties in the Council were roused to the highest pitch of passion, the proceedings, especially during the early sessions, were very tumultuous, until the lay commissioners and senators had to urge the bishops to keep order, saying that such Ἐκβοήσεις Δημοτικαί (vulgar outcries) were disgraceful. (See the account from Mansi, cited by Stanley, Eastern Church, lect. 2, p. 165.)

At the first session (October 8, 451) the Council assembled in the Church of St. Euphemia; in the center sat the officers of the emperor; at their left, or on the epistle side, sat the bishops of Constantinople, Antioch, Caesarea in Cappadocia, and of the other Eastern dioceses, and Pontus, Asia, and Thrace, together with the four legates; on the other side were Dioscurus, Juvenal, Thalassius of Csesarea, and the other bishops; of Egypt, Palestine, and Illyria, most of whom had been present in the pseudo-council of Ephesus. In the midst were the Holy Gospels, placed upon a raised seat. When they had taken their seats, the legates of the pope demanded that Dioscurus should withdraw from the assembly, accusing him of his scandalous conduct tat Ephesus, and declaring that otherwise they would depart. Then the imperial officers ordered him to withdraw from the Council, and to take his seat among the accused. The acts of the so-called "Robber Council" of Ephesus (q.v.) were discussed and condemned, and Dioscurus was left with only twelve bishops to stand by him. The Eutychian heresy, that in our Lord were two natures before his incarnation, and but one afterwards, was anathematized. The majority of the assembled bishops then proceeded to anathematize Dioscurus himself, and demanded that he, together with Juvenal of Jerusalem, Thalassius of Caesarea, Eusebius of Ancyra, Eustachius of Berytus, and Basil of Seleucia, who had presided at the Council, should be deposed from the episcopate. (See Dioscurus).

At the second session (Oct. 10), the following exposition of faith, substantially taken from a letter of Leo to Flavianus, was approved, and its opponents anathematized: "The divine nature and the human nature, each remaining perfect, have been united in one person, to the intent that the same Mediator might die, being yet immortal and impassible... Neither nature is altered by the other; he who is truly God is also truly man... The Word and the flesh preserve each its proper functions. Holy Scripture proves equally the verity of the two natures. He is God, since it is written, 'In the beginning was the Word, and the Word was God.' He is also man, since it is written, 'The Word was made flesh, and dwelt among us.' As man, he was tempted by the devil; as God, he is ministered unto by angels. As man, he wept over the tomb of Lazarus; as God, he raised him from the dead. As man, he is nailed to the cross; as God, he makes all nature tremble at his death. It is by reason of the unity of person that we say that the Son of Man came down from heaven, and that the Son of God was crucified and buried, although he was so only as to his human nature."

At the third session the deposition of Dioscurus was pronounced irrevocable, and soon after he was banished to Gangra, in Paphlagonia, where, in the course of three years, he died.

In the fifth session the following formula of faith on the question at issue was adopted: "We confess and with one accord teach one and the same Son, our Lord Jesus Christ, perfect in the divinity, perfect in the humanity, truly God and truly man, consisting of a reasonable soul and body; consubstantial with the Father according to the Godhead, and consubstantial with us according to the manhood; in all things like unto us, sin only excepted; who was begotten of the Father before all ages, according to the Godhead; and in the last days, the same was born according to the manhood, of Mary the Virgin, mother of God, for us and for our salvation; who is to be acknowledged one and the same Christ, the Son, the Lord, the only begotten in two natures, without mixture, change, division, or separation; the difference of natures not being removed by their union, but rather the propriety of each nature being preserved and concurring in one person and in one Ὑπόστασις , so that he is not divided or separated into two persons, but the only Son, God, the Word, our Lord Jesus Christ, and one and the same person." At the later sessions (9-15) a number of questions of order, supremacy, discipline, etc. were settled. But by far the most important was the 28th canon, sess. 15, by which the patriarch of Constantinople was placed on equality of authority with the bishop of Rome, saving only to the latter priority of honor. The Roman delegates protested against this, and, after its adoption, Leo constantly opposed it, upon the plea that it contradicted the sixth of Nicaea, which assigned the second place in dignity to Alexandria; however, in spite of his opposition and that of his successors, the canon remained and was executed. (See Supremacy Of The Pope).

The acts of this Council in Greek, with the exception of the anathemas, are loqt. See Evagrius, Hist.  Ecclesiastes 2:4; Labbe and Cossart, Concilia, tom. 4; Mansi, Concilia, 6:590; Landon, Man. of Councils, p. 113-127; Gieseler, Church History (Cunningham's), 1:240; Mosheim, Church History, bk. 2, cent. 5, pt. 2, ch. 5, § 15, 16; Neander, Church History, 2:518, 524; Hefele, Conciliengeschichte, 2:392; especially Dorner, Person of Christ (Edinburgh, div. 2, vol. 1, p. 93-106); Schaff, Church Hist. 2, § 56, 65; 2, § 141; Shedd, History of Doctrines, 1:398 sq.; Elliott, Delineation of Romanism, bk. 3, ch. 3, 11. (See Christology); (See Councils); (See Eutyches); (See Nestorianism).

The Nuttall Encyclopedia [2]

A city of Bithynia, at the entrance of the Thracian Bosphorus, where the fourth Council of the Church was held in 451, which defined the orthodox conception of Christ as God-man.