(or ECDI'DIUS), son of Isicius, archbishop of Vienne, was born about the middle of the 5th century. From his earliest years he is said to have devoted himself to literature, and to have given promise of that erudition which subsequently gained for him, among his countrymen at least, the reputation of being the most profound and eloquent scholar of his age. After bestowing an ample inheritance on the poor, lie retired into the monastery of St. Peter and St. Paul, close to the walls of his native city, and remained in the seclusion of the cloister until the death of his father (in A. D. 490), whom he succeeded in the archiepiscopal dignity. His fame as a pious and charitable priest and a powerful controversialist now rose very high. He took part in the celebrated conference at Lyons between the Arians and the Catholic bishops, held in the presence of the Burgundian king, where, as we are told, he silenced the heretics and brought back many waverers to the bosom of the church. Gundebald himself is said to have yielded to his arguments, although from political motives he refused to recant his errors openly; and all agree, that after his death his son Sigismund publicly declared his adherence to the true faith. Avitus, at the request of his royal admirers, published treatises in confutation of the Nestorians, Eutychians, Sabellians, and Pelagians, and was peculiarly successful in gaining over a number of Jews who had settled in his diocese. By pope Hormisda he was appointed vicar apostolic in Gaul, in the year 517 presided at the council of Epaune (concilium Epaonense), died on the 5th of February, 523, was buried in the monastery of St. Peter and St. Paul, where he had passed so many years of his early life, and in the fulness of time received the honours of canonization.