 In that time , the Christian faith was shaken by the contrast between Miaphysites and Chalcedonians . These were two opposing christological positions ; the Chalcedonians claimed that Christ had both human and divine natures , while the Miaphysites claimed he had only one single united nature . The Council of Chalcedon , convoked by Emperor Marcian in 451 , had ruled out Miaphysitism , with the support of the pope in the West and many bishops in the East . However , the Miaphysite position was still strong : the two Miaphysite Patriarchs Timothy Aelurus of Alexandria and Peter the Fuller of Antioch were deposed . 
