That the composition of a history of the Church was Eusebius’ own idea, and was not due to any suggestion from without, seems clear, both from the absence of reference to any one else as prompting it, and from the lack of a dedication at the beginning of the work. The reasons which led him to undertake its composition seem to have been both scientific and apologetic. He lived, and he must have realized the fact, at the opening of a new age in the history of the Church. He believed, as he frequently tells us, that the period of struggle had come to an end, and that the Church was now about entering upon a new era of prosperity. He must have seen that it was a peculiarly fitting time to put on record for the benefit of posterity the great events which had taken place within the Church during the generations that were past, to sum up in one narrative all the trials and triumphs which had now emerged in this final and greatest triumph, which he was witnessing. He wrote, as any historian of the present day would write, for the information and instruction of his contemporaries and of those who should come after, and yet there was in his mind all the time the apologetic purpose, the desire to exhibit to the world the history of Christianity as a proof of its divine origin and efficacy. The plan which he proposed to himself is stated at the very beginning of his work: “It is my purpose to write an account of the successions of the holy apostles, as well as of the times which have elapsed from the days of our Saviour to our own; and to relate how many and how important events are said to have occurred in the history of the Church; and to mention those who have governed and presided over the Church in the most prominent parishes, and those who in each generation have proclaimed the divine word either orally or in writing. It is my purpose also to give the names and the number and the times of those who through love of innovation have run into the greatest errors, and proclaiming themselves discoverers of knowledge, falsely so-called, have, like fierce wolves, unmercifully devastated the flock of Christ. It is my intention, moreover, to recount the misfortunes which immediately came upon the whole Jewish nation in consequence of their plots against our Saviour, and to record the ways and the times in which the divine word has been attacked by the Gentiles, and to describe the character of those who at various periods have contended for it in the face of blood and tortures, as well as the confessions which have been made in our own days, and finally the gracious and kindly succour which our Saviour afforded them all.” It will be seen that Eusebius had a very comprehensive idea of what a history of the Church should comprise, and that he was fully alive to its importance.
