St. Athanasius: Four Discourses Against the Arians

Athanasius of Alexandria (Greek: Ἀθανάσιος, Athanásios) (c. 293 – 2 May 373), also given the titles Athanasius the Great, Pope Athanasius I of Alexandria, and Athanasius the Apostolic, was a Christian theologian, bishop of Alexandria, Church Father, and a noted Egyptian leader of the fourth century. He is best remembered for his role in the conflict with Arius and Arianism. At the First Council of Nicaea, Athanasius argued against Arius and his doctrine that Christ is of a distinct substance from the Father.

Athanasius is a Doctor of the Church in the Catholic Church in communion with the Bishop of Rome, and he is counted as one of the four Great Doctors in the Eastern Orthodox Christian tradition. Athanasius' feast day is 2 May in Western Christianity, 15 May in the Coptic Orthodox Church, and 18 January in the other Eastern Orthodox churches.