The earliest evidence for Christian teaching comes from Saint Paul's letters, written from the 50s up to 66 or so (when he probably died in the persecution by Nero). These letters show that some fairly definite beliefs about Christ's teaching were already taken for granted among Christian communities. Paul sharply distinguishes the teaching of Christ from his own inferences from it. He plainly expects members of the Church to assume that Christ had taught definite doctrines, and to have firm and undisputed views about what the doctrines were. 4 Paul's letters, then, show Christian teaching (oral or written) in a fairly developed state in the mid 60s. Other evidence of Christian teaching at this time may be found in the earlier versions of the two written accounts of the life and teaching of Christ, by Saint Mark and Saint Luke, if these versions were written (as they probably were) before the death of Paul.

Beyond this there is very little evidence to help us to date the New Testament books, or to check the accuracy of their contents. We have good reasons to place the Gospels between 65 and 100, but no clear reason for preferring any more definite dates. In particular, we have no historical reason for believing that the fourth Gospel is much later than the first three ('Synoptic') Gospels. Belief in its lateness rests on the argument that it is more influenced by Greek philosophy than the Synoptic Gospels are, and therefore must be later. Both the premisses and the inference in this line of argument are open to doubt.

After the New Testament, the 'Apostolic Fathers' come first in the long sequence of early Christian writers. They show that in the second century the Church had organized worship, sacraments, orders of ministry, and doctrinal standards. In this period the conflict between Christianity and the Roman authorities led to persecution--sporadic and unsystematic, but sometimes severe. The persecutions continued until the Edict of Milan, enjoining toleration, was issued in 313 by Constantine, the first Christian emperor. From then on the Church gradually acquired the status of an established religion, using its relief from persecution to persecute non-Christians and heretical or schismatic Christians.

While the Church expanded, and improved its position in society, it also formulated its doctrines. The Catholic doctrine emerged from conflicts and heresies that eventually forced decisions on doctrinal questions. Though the doctrinal definitions did not end dispute in the Church, they formed a body of orthodox teaching expressing the rational commitments of a Christian believer. The Councils of Nicaea (325) and Chalcedon (451) more or less define the period of fundamental theological argument and definition. . .