Why This History Tells of the Wars

Before we begin the fifth book of our history, we must ask those who read this work not to blame us too hastily if, having set out to write a history of the church, we still mix in with church affairs an account of the wars that took place in this period, so far as they could be properly verified. We have done this for several reasons. First, to lay the facts exactly before our readers. Second, so that their minds would not grow weary of hearing over and over about the quarrels of bishops and their schemes against one another. But most of all, to make it plain that whenever the affairs of the state were disturbed, the affairs of the church, as if by some living sympathy, fell into disorder too. [a]

In fact, anyone who looks carefully into the matter will find that the evils of the state and the troubles of the church have been bound up together. He will see that they have either arisen at the same time or followed immediately one after the other. Sometimes the church’s troubles come first and upheavals in the state follow; sometimes it is the other way around. So I cannot believe that this constant alternation is mere chance. I am persuaded that it comes from our sins, and that these evils are laid on us as punishment we have earned, if indeed, as the apostle truly says, “The sins of some people are plain beforehand, going ahead of them to judgment; and the sins of others follow after them.”

That is why we have woven many affairs of state into our church history. Of the wars fought in the reign of Constantine we have said nothing, because, owing to their wickedness, we found no account of them that could be relied on. But later events, as much as we could learn of them from people still living, we have gone through quickly in the order in which they happened. We have kept the emperors in this history throughout, because from the time they began to profess the Christian religion the affairs of the church have depended on them, so much so that even the greatest synods have been called, and still are called, at their command. Finally, we have paid particular attention to the Arian heresy, because it has so greatly troubled the churches. Let these remarks be enough by way of preface. We will now go on with our history.