Roman Catholicism comprises the beliefs and practices of the Roman Catholic Church. It stands under the authority of the bishop of Rome, the pope, and is led by him and bishops who are held to be, through ordination, successors of Peter and the apostles. Doctrine and sacraments are administered by the hierarchy of archbishops, bishops, priests, and deacons. As successor to Peter, the pope is considered the Vicar of Christ. Roman Catholics believe their church to be the one, holy, catholic, and apostolic church, possessing all the properties of the one, true church of Christ.
The faith of the church is understood to be identical with that taught by Christ and his apostles and contained in the Bible and tradition. New definitions of doctrines, such as the Immaculate Conception of Mary (1854) and the bodily Assumption of Mary (1950), have been declared by popes, however. At Vatican Council I (1870) the pope was proclaimed “endowed with infallibility, ex cathedra, in other words, when exercising the office of pastor and teacher of all Christians.”
The center of Roman Catholic worship is the celebration of the Mass, the Eucharist, which is the commemoration of Christ's sacrificial death and resurrection. Other sacraments are baptism, confirmation, penance, matrimony, anointing of the sick (formerly known as extreme unction), and holy orders. The Virgin Mary and the other saints, and their relics, are venerated, and prayers are made to them to intercede with God, in whose presence they are believed to dwell.
The Roman Catholic Church is the largest Christian organization in the world, found in most countries.
Vatican Council II (1962–1965) sought to “update” the church, bringing about changes in practice and more deeply involving the laity. The immensely popular Pope John Paul II (1978–2005) took a more conservative course and reached out to Catholics worldwide through his extensive travels.
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