There never was during the first three centuries an absolutely identical canon accepted throughout all Christendom. Some churches, as we have seen, received books which others did not receive. But we must be careful not to exaggerate these differences. The marvel was not that they existed, but that they were so few. By far the greater part of the New Testament was received by Christians everywhere undoubtingly; and as to the rest, though we cannot explain in detail every difference of usage, we can readily see that such differences were almost inevitable. Copies had to be multiplied by the slow, laborious, and expensive process of handwriting. The mere cost of copying must have impeded the circulation of the New Testament among an oppressed and poor people, as the Christians for the more part were.
And yet the early Church possessed in common a complete code of Christian doctrine, and valued it as her most precious treasure. That treasure she guarded with the utmost jealousy, and any attempt to tamper with it she visited with the most severe penalty which she could inflict. With respect to the Four Gospels, the Epistles of S. Paul, and some others, there was never any doubt from the very first. As to other books we know that the churches exercised vigilant caution, and discussed in frequent councils the claims of writings which professed to be apostolic.
The general result of our inquiries may be fairly stated as follows:-
By far the greater part of the books now deemed canonical were accepted by the first Christians universally.
Two books accepted universally in the East were only partially accepted in the West; and three, or perhaps four other books accepted universally in the West, were only partially accepted in the East.
But the books partially accepted by the one branch of the Church were never formally rejected by the other branch.
These conclusions comprise all the books now deemed canonical, with one exception- the Second Epistle of Peter, which does no appear to have been adopted by either the Eastern or Western Church in the first and second centuries.
from pages 372- 373, 1st Century of Christianity