The spread of Christianity was assisted by a special literature, such as was produced by no other ancient church save that of the Jews. The teaching of Jesus which, at first, was preserved by oral tradition only, was soon set down in written records, of which the four Gospels, dating from c. 65* to 100, eventually came to be accepted as authoritative. By the time of Constantine, these four books, together with other early records and epistles, had been codified so as to form the “New Testament,” and the whole of this collection was made accessible to the western peoples in several Latin versions. The task of revising and amplifying the Christian creed in the light of other systems of thought and, notably, of the Stoic and Platonic philosophies, was begun in the epistles of Paul and carried on in the writings of various church fathers, mostly of Greek nationality, among whom the Alexandrian bishops Clement and Origen (c. 200) were the pioneers. From the time of M. Aurelius, the church also kept its own historical records, among which the Acts of the Martyrs came to form a library in themselves. In the days of Constantine, a Palestinian bishop named Eusebius (264-340) collected the various traditions into a standard history of the church. The same scholar also correlated the dates of Judeo-Christian events with those of Oriental, of Greek, and of Roman history in synchronistic tables which are of considerable importance for our general knowledge of ancient chronology.
From: A History of Rome Down to the Reign of Constantine by M. Cary; 2nd edition (London: Macmillan & Co., Ltd., 1954), pp. 763-764. The first edition was published in 1935.
*This early date should be brought down to the late 40s. – RZ