The First Centuries of Christianity

This page forms part of a brief outline of some of the aspects of Christianity about which some readers of AWE may want to know more. It is written in a sequence that you may want to follow. The best place to start, if you want to follow the whole course, is Principal Christian Denominations. Many users of AWE will come to this group of articles only wanting to know more about one of the denominations mentioned, or by way of links from other places. You should of course read a larger book if you are taking a serious interest in the Christian religion - our articles are the merest sketches of what is a vast array of complex ideas.

In the decades after the death of Jesus Christian missionaries, of whom the most famous was St. Paul (d. 64 CE), brought Christianity westward from Palestine to Asia Minor, Greece, and Italy, and within two centuries there were groups of Christians in most parts of the Roman Empire. There was at this time no formal agreement about the core beliefs of Christianity, and there were in fact significant differences of belief amongst those who regarded themselves as Christians. Towards the end of the second century, however, St. Irenaeus (died c 202 CE), the bishop of Lugdunum (modern Lyons in France), in his disputes with the Gnostics, who were committed to a form of Christian mysticism, argued that disagreements about doctrine within a particular locality were to be settled by the head of the church (i.e. the bishop) within that locality, and that it was for councils (i.e. meetings of bishops) to determine what was true and what was false in religious matters, i.e. to distinguish orthodoxy from heresy. Irenaeus also maintained that the bishop of Rome, as the successor of St. Peter, the first bishop of Rome, should take precedence over the other bishops.

For nearly 300 years the Christians were no more than a minor sect within the Roman Empire and from time to time subject to persecution by the authorities, but after the conversion of the emperor Constantine in 312, the situation changed. Christians were granted freedom of worship by the Edict of Milan (313); the number of Christians increased dramatically; Christianity was adopted by many members of the ruling class, and at the end of the fourth century was declared the official religion of the Roman Empire by the emperor Theodosius (r. 394-395). By this time the empire had for nearly a century 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; and the Christian Church, especially after Christianity became the official religion of the Roman Empire, tended in its organisation and in other ways to reflect these differences, the Western Church using Latin in its services and recognising the primacy of the bishop of Rome (the Pope), and the Eastern Church using Greek in its services and recognising the primacy of the Patriarch (i.e., the bishop) of Constantinople.

At the end of the fifth century the Western Empire, which had been under attack for many years from Goths, Vandals, Huns, and other tribes from the north, collapsed. The Eastern Empire, however, remained intact and continued to flourish under the rule of the emperor in Constantinople. All this led to further differences between the eastern and western halves of the Church, since in many areas of western Europe, in the absence of a stable government, the Church took over some of the functions of the civil authority, whereas in the east the bishops and clergy were always subject to the authority of the secular government.