John of Damascus

John of Damascus (c. 675–749), a monk near Jerusalem, is reckoned the last of the Greek Fathers. His Fount of Knowledge — especially its third part, An Exact Exposition of the Orthodox Faith — systematised patristic theology, and his treatises in defence of icons shaped the outcome of the iconoclast controversy. A Doctor of the Church.

Reckoned the last of the Greek Fathers, John gathered the whole patristic inheritance into system. His Exact Exposition of the Orthodox Faith became the East's standard summary of doctrine and a model for later Western summae, and his defence of sacred images during the iconoclast crisis shaped the church's understanding of how the invisible God may be honoured in the incarnate Son. His hymns are still sung in the Eastern liturgy.