It is the largest Christian Church, dominant particularly in South America and southern Europe. Roman Catholicism differs from Protestantism in the importance it grants to tradition, ritual, and the authority of the Pope as successor to the Apostle St Peter, and especially in its doctrines of papal infallibility (formally defined in 1870) and of the Eucharist (transubstantiation), its celibate male priesthood, its emphasis on confession, and the veneration of the Virgin Mary and other saints. Much modern Roman Catholic thought and practice arises from scholastic theology and from the response to the Reformation made by the Council of Trent (1545–63). It became less rigid after the Second Vatican Council (1962-5), but its continuing opposition to divorce, abortion, and artificial contraception remains controversial