Ignatius Brianchaninov was a 19th-century monk and the abbot of the St. Sergius Monastery in St. Petersburg, Russia. He is the author of On the Prayer of Jesus. Kallistos Timothy Ware is an Orthodox Bishop of the Ecumenical Patriarchate of Constantinople and the retired Spalding Lecturer in Eastern Orthodox Studies at Pembroke College, University of Oxford. He is best-known as the author of the classic text The Orthodox Church.