St. John Damascene was the great defender of the veneration of images against the iconoclasts, the destroyers of statues and pictures of the saints. He was a learned theologian and carefully gathered together and transmitted to us the teaching of the Greek Fathers and is thus one of the most trustworthy witnesses to oriental tradition. He also is the author of liturgical hymns which are still in use. He died in 749. Leo XIII proclaimed him a Doctor of the universal Church.