Pope Sergius I
Meanwhile, the Emperor's bloody persecution of the Manichaeans and suppression of popular traditions of non-Chalcedonian origin caused dissension within the Church. In 692 Justinian convened the so-called Quinisext Council at Constantinople to put his religious policies into effect. The Council expanded and clarified the rulings of the Fifth and Sixth ecumenical councils, but by highlighting differences between the Eastern and Western observances (such as the marriage of priests and the Roman practice of fasting on Saturdays) the council compromised Byzantine relations with the Roman Church. The emperor ordered Pope Sergius I arrested, but the militias of Rome and Ravenna rebelled and took the Pope's side.