675, probably in Damascus, Syria.
December 4, circa 749, at Mar Saba, his monastery between Jerusalem and the Dead Sea.
Of a good family in Damascus, John was educated by the elder Cosmas, along with his foster brother, Cosmas the Melodist. He held some office under the Caliph, and later retired to the laura of St. Sabas, near Jerusalem, along his foster brother. There he wrote his theological works and hymns, and was ordained a priest of the church of Jerusalem late in life. His enemies called him Mansur, for reasons unknown. His three orations in favor of icons earned him the sobriquets Chrysorrhous and The Doctor of Christian Art. His works include: