Saint John of Damascus

John of Damascus was the last of the Greek Fathers, a monk of the desert monastery of Mar Saba near Jerusalem, living under Muslim rule. When the Byzantine emperors launched their campaign against religious images, John — safely beyond their reach — became the great defender of the icons, arguing that because God had taken flesh, the Christian may honour holy images of Christ and the saints. His Fount of Knowledge, whose third part expounds the whole of the faith, was the first great systematic theology of the Greek Church.