This icon of St. Cosmas is from the Katholikon of All Saints in the Monastery of Barlaam in Meteora. St. Cosmas was the foster brother of St. John of Damascus, and lived in the 8th century. With his brother St. John, St. Cosmas was taught by the former slave Cosmas, a learned Sicilian and a writer of church hymns. Both of them, truly brothers in spirit, entered the monastery of St. Sabba the Sanctified in a wadi near Jerusalem.
St. Cosmas, at the urging of his brother, also wrote in defense of the icons during the Iconoclastic persecutions of those who correctly defended the proper and necessary use of icons in Orthodox life and worship. St. Cosmas also wrote church hymns for the church services, many which have been preserved until today. Called by God to His service as a bishop, St. Cosmas left St. Sabba’s Monastery in a.d. 743 and was made the bishop of Maiuma, the port of Gaza on the southern coast of Phoenicia, where he served for many years. After a long life of service, prayer, self-restraint, and pouring out his heart in beautiful church hymnology, St. Cosmas went to the Lord in a.d. 787.