Saint John Damascene, Priest and Doctor of the Church

John was born about 675 in Damascus into the Christian Mansur family, which served the Umayyad caliphs as financial officials, and he himself held office at the caliph's court. Later he became a monk at the monastery of Mar Saba near Jerusalem and was ordained priest. When the Iconoclast emperors in Constantinople forbade the veneration of icons, John, living beyond their reach under Muslim rule, wrote three treatises in their defence. His Fount of Knowledge, with its exposition of the faith, gathered the teaching of the earlier Fathers and was long used as a textbook, in the West as well. Many hymns of the Eastern liturgy are ascribed to him, among them the canon of Easter. He died about 749. Leo XIII declared him a Doctor of the Church in 1890.