The First Council Of Nice, according to the most probable account, opened on May 20, 325, and closed on Aug. 25; according to others, it lasted from June 9 to the end of July. It is of universal and permanent interest, both for the great sig-niticance of the subjects brought before it and the lasting influence of its determinations, and as the beginning of active participation on the part of the secular power in measures affecting the doctrine and discipline of the church. The letters summoning the bishops were issued by the emperor Constantine, and the sixth general council (680) expressly declares that it was convened by him and Sylvester, bishop of Rome; but the statement as regards Sylvester is disputed. The object of convocation was to suppress the Arian heresy and the schism of Me-letius in Egypt, and to settle the differences about the proper time of celebrating Easter. About 318 bishops, nearly all orientals, with inferior clerics to the number of 2,000, attended. The emperor was present at the principal sessions, which were held in a church up to July 3, and afterward in a hall of the imperial palace prepared for the purpose. The question of who were the presiding officers is much disputed.
Baronius, with the latest historian of the council, Hefele, and Roman Catholic writers generally, contend that Hosius, bishop of Cordova, with the Roman priests Vitus and Vincentius, presided as the legates of Sylvester, pointing out that in all the lists of signatures extant the names of these three personages precede all the others. But Tillemont and most Protestant historians deny the fact of their having so presided. According to the Greek historian Socrates, the interval between May 20 and the first solemn session of June 14 was occupied in discussing the doctrines of Arius, who was supported by 15 bishops, chief among whom were Eusebius of Nicomedia and Theognis of Nice. The orthodox bishops had for spokesmen Athanasius, then archdeacon of Alexandria. Alexander, a priest of Constantinople, and Marcellus, bishop of Ancyra. The Semi-Arian or middle party was represented by the historian Eusebius, bishop of Crcsarea, and thence called Eusebians. (See Arianism.) Two formula- of belief were submitted and discussed.
The one, drawn up by Eusebius of Caesarea, was characterized by the omission of the word "consubstantial," intended to express that the Son was begotten of the Father's substance; the other, of unknown authorship, was adopted by the council, and has since been known as the "Nicene Creed." In the most ancient and authentic form it corresponds with this latter as far as the words " and in the Holy Ghost." After these is added a solemn anathema formally condemning the chief points of the Arian doctrine. The remaining articles of the Nicene creed, as we now have it, were added subsequently by the council of Constantinople in 381, with the exception of the words "and from the Son " (filioque), after the clause "who proceedeth from the Father." The filloque was added by the western churches, first in Spain, then in Gaul and Germany, about the 5th century, and adopted by the church of Rome in 1014, though by no formal and official declaration. The Easter controversy and the Meletian schism were then disposed of, and 20 canons were enacted regulating various points of church discipline; among others, the jurisdiction of the great patriarchal sees.
A law was also introduced compelling married clerics to separate from their wives, but was withdrawn at the remonstrance of the Egyptian confessor Paphnutius.
The Seventh General Council, convened by the empress regent Irene, with the concurrence of Pope Adrian I., to condemn the errors and excesses of the Iconoclasts. (See Icoxoclasts.) The council first met in Constantinople Aug. 1, 786, but, on account of the violent opposition it met with, was adjourned to Nice, where it opened Sept. 24, 787, and closed Oct. 13. From 330 to 387 bishops, besides about 130 abbots, attended. Tarasius, patriarch of Constantinople, presided. Seven sessions were held. It was decreed that the cross, and images in colors, or in mosaic work or any other material, of Christ, his mother, saints, and holy men, might be set up on walls and tablets, in churches, houses, and highways, and used on sacred vessels and vestments; and that they should be treated as pious memorials, venerated, and kissed, but not with the honor and worship due to God alone.