Christian teacher; d. 373; ordained as a deacon in Egypt around 319, Athanasius attended the Council of Nicaea in 325 and soon afterward became the overseer (bishop) of Alexandria. Athanasius spent much of his career confronting Arius's teaching that Jesus is not God.

In 367 he wrote a letter (now referred to as the thirty-ninth Festal Letter) to the churches in his area, listing the books meeting the standards set for the New Testament canon (i.e., authoritative writ-ings) — identical to the list that Christians still use today. See also Arius of Alexandria; canon; Christology; church fathers; Constantine the Great; Council of Nicaea.