His Excellency Kallistos Ware was the Orthodox Metropolitan Bishop of Diokleia. As an Orthodox monk, he spent many years at monasteries in Greece. A highly respected theologian, he lectured in Eastern Orthodox Studies at Oxford University for 31 years and was a Fellow of Pembroke College. The Orthodox Church is his best-known work. Together with colleagues he  translated into English four of the five volumes of the Philokalia, an important collection of sacred writings in the Orthodox tradition.