Roman Catholic Church
The Roman Catholic Church is the oldest of the Christian churches, claiming continuity with the church established by the founder of Christianity, Jesus. It acknowledges as its head the pope, i.e., the bishop of Rome, whom it sees as the legitimate successor of St. Peter, the first bishop of Rome, who was appointed by Jesus as the head of his church. Although only a minority of Christians in the United Kingdom are Roman Catholics, worldwide the Roman Catholic Church is the largest of the Christian denominations with more than a billion members. The expression 'Roman Catholic', either as a noun phrase or as an adjectival phrase, may be used to refer to a member of the Roman Catholic Church, and the set of doctrines on which the Roman Catholic Church is based is known as Roman Catholicism. Sometimes, though not always, the word 'Catholic' by itself is equivalent to 'Roman Catholic'. (For the different ways in which the word 'catholic' is used see catholic.)
At the end of the fourth century CE Christianity became the official religion of the Roman Empire, which had by then been divided for administrative purposes into two halves - a Latin-speaking western half with Rome as its capital and a Greek-speaking eastern half with Constantinople as its capital. The Christian Church tended in various ways to reflect these differences: e.g., in the west it used Latin in its services, while in the east it used Greek. The Church was, however, still a single church, acknowledging the overall supremacy of the bishop of Rome, the pope. Over the centuries there were disagreements between the eastern and western halves of the Church about doctrine and about the extent of papal authority, and these led in 1054 to the Great (East-West) Schism, sometimes referred to simply as the Great Schism, a formal break between east and west, the eastern half of the Church becoming the Orthodox Church (or Byzantine Church) with the Patriarch of Constantinople at its head, and the western half becoming the Roman Catholic Church with the pope, the bishop of Rome, at its head.
During the Middle Ages the Roman Catholic Church was the only church in Western Europe, and the pope, as well as being the spiritual head of the church, was also a significant figure in European political and diplomatic life - not least because he was the temporal ruler of the Papal States, a collection of city-states which between them covered a large part of Central Italy. However, in the fifteenth century there was growing dissatisfaction with some of the Church's practices and anger at the corruption of its clergy - grievances articulated by Martin Luther (1483-1546), a German priest and professor of Theology at Wittenberg University, who in 1517 nailed to the door of Wittenberg Cathedral a document which demanded reform (The Ninety-five Theses). The Church refused to accommodate Luther's demands and excommunicated him; and this resulted, in the course of the sixteenth century, in the establishment of Protestant churches, separate from the Roman Catholic Church, throughout most of Europe. (Since the sixteenth century the majority of Christians in northern Europe have belonged to one or other of the Protestant denominations, though in the south (i.e., in France, Spain, Portugal, Italy, and southern Germany) Roman Catholicism has maintained its dominance.)
In the sixteenth and seventeenth centuries, to meet the criticisms of those who remained within the Church and to combat the spread of Protestantism, the Roman Catholic Church carried out its own programme of reform (referred to by historians as the Counter-Reformation or the Catholic Reformation). A decisive step in this programme was the Council of Trent, an ecumenical council, i.e., a council of bishops from all the Catholic dioceses, which was summoned in 1545 by Pope Paul III (reigned 1534-1549) and continued until 1563. The Council of Trent addressed certain abuses in the practices of the Church, ensured that the clergy were subject to stricter discipline, and clarified Roman Catholic doctrine in the face of the challenge of Protestantism.
There have been twenty one ecumenical councils in the history of the Church. The first, in 325, was the Council of Nicaea, which formulated the Nicene Creed, and the two most recent have been the First and Second Vatican Councils. The First Vatican Council (1869-1870) is noted for its definition of the doctrine of papal infallibility, while the Second Vatican Council (1962-1965), summoned by Pope John XXIII (1881-1963, reigned 1958-1963), sought to reform and modernise the Church. It decreed, among other things, that the Mass was no longer to be celebrated in Latin, but in the vernacular, i.e., the language of the country in which the Mass was being celebrated.
Doctrine and Practice
Roman Catholicism holds that not only the Bible but the traditions of the Church are sources of truth in religious matters. It teaches that salvation depends on both faith and 'works', i.e., both on belief in Jesus and on the quality of a person's life and his or her acceptance of the sacraments. Mortal sins, i.e., serious transgressions of God's law (by contrast with venial, i.e., excusable, sins) involve a loss of 'grace' and, unless repented, imperil a person's salvation.
Roman Catholicism holds that an individual's relationship with God need not always be direct, but may be mediated through the institution of the Church itself and also through the 'saints', i.e., individuals who have lived lives of exemplary holiness and who after death have the power to intercede on the individual's behalf with God. Occupying a specially exalted position among the saints is St. Mary, the mother of Jesus, who is the focus of particular devotion among Catholics.
Roman Catholic religious services are typically more formal and elaborate than the services in most Protestant churches, though since the Second Vatican Council (1962-65) this is less so. Partly because of the belief in saints as mediators of the relationship between the individual and God, Roman Catholic churches tend to be more richly decorated than Protestant churches, and normally contain , e.g., statues of saints and other objects of devotion.
By contrast with almost all other Christian denominations nowadays, the Roman Catholic clergy is all male and celibate, i.e., unmarried and committed to chastity. Although the Catholic hierarchy has been reluctant to change the rule of priestly celibacy, it is agreed that it has no scriptural basis, and in fact for the first millennium of the Christian era married priests were not uncommon - the rule requiring celibacy dates only from 1139.
The Roman Catholic Church has a strongly hierarchical structure. At the most basis level are the parishes, each parish consisting of the members of the Church in a particular locality and the priest who has care of them. The different parishes in an area are under episcopal authority, i.e., under the authority of a bishop, the area over which the bishop has authority being known as a diocese (pronounced DY-er-sis, IPA: /ˈdaɪəsɪs/) - in the Roman Catholic Church worldwide there are today 2795 dioceses. The dioceses in a particular region or country are grouped together under an archbishop, e.g., the various dioceses in England all fall within the jurisdiction of the Archbishop of Westminster. At the head of the Church, with authority throughout the dioceses worldwide, is the bishop of Rome, the pope, who has his official residence in the Vatican, a small independent state within the city of Rome. The pope is assisted in his government of the Church by the cardinals, i.e., bishops specially selected by the pope to act as his counsellors and to supervise the administration of the Church. The cardinals rank next in authority after the pope, and on the death of a pope it is the College of Cardinals that chooses his successor. (The word 'cardinal' comes from the Latin cardinalis, which is the adjective from cardo (a hinge) and means: relating to a hinge, i.e., something on which something else depends, and hence: chief or principal.)
See further Principal Christian Denominations.