1911 Encyclopædia Britannica/Hosius
HOSIUS, or Osius (c. 257–359), bishop of Cordova, was born about A.D. 257, probably at Cordova, although from a passage in Zosimus it has sometimes been conjectured that he was believed by that writer to be a native of Egypt. Elected to the see of Cordova before the end of the 3rd century, he narrowly escaped martyrdom in the persecution of Maximian (303-305). In 305 or 306 he attended the council of Illiberis or Elvira (his name appearing second in the list of those present), and upheld its severe canons concerning such points of discipline as the treatment of the lapsed and clerical marriages. In 313 he appears at the court of Constantine, being expressly mentioned by name in a constitution directed by the emperor to Caecilianus of Carthage in that year. In 323 he was the bearer and possibly the writer of Constantine’s letter to Bishop Alexander of Alexandria and Arius his deacon, bidding them cease disturbing the peace of the church; and, on the failure of the negotiations in Egypt, it was doubtless with the active concurrence of Hosius that the council of Nicaea was convened in 325. He certainly took part in its proceedings, and was one of the large number of “confessors” present; that he presided is a very doubtful assertion, as also that he was the principal author of the Nicene Creed. Still he powerfully influenced the judgment of the emperor in favour of the orthodox party. After a period of quiet life in his own diocese, Hosius presided in 343 at the fruitless synod of Sardica, which showed itself so hostile to Arianism; and afterwards he spoke and wrote in favour of Athanasius in such a way as to bring upon himself a sentence of banishment to Sirmium (355). From his exile he wrote to Constantius II. his only extant composition, a letter not unjustly characterized by the great French historian Sebastian Tillemont as displaying gravity, dignity, gentleness, wisdom, generosity and in fact all the qualities of a great soul and a great bishop. Subjected to continual pressure the old man, who was near his hundredth year, was weak enough to sign the formula adopted by the second synod of Sirmium in 357, which involved communion with the Arians but not the condemnation of Athanasius. He was then permitted to return to his diocese, where he died in 359.
See S. Tillemont, Mémoires, vii. 300–321 (1700); Hefele, Conciliengeschichte, vol. i.; H. M. Gwatkin, Studies of Arianism (Cambridge, 1882, 2nd ed., 1900); A. W. W. Dale, The Synod of Elvira (London, 1882); and article s.v. in Herzog-Hauck, Realencyklopädie (3rd ed., 1900), with bibliography.