Life of Constantine

It is also worthy of record that about the time of which I am at present writing, the emperor, having heard of an insurrection of some barbarians in the East, observed that the conquest of this enemy was still in store for him, and resolved on an expedition against the Persians. Accordingly he proceeded at once to put his forces in motion, at the same time communicating his intended march to the bishops who happened to be at his court, some of whom he judged it right to take with him as companions, and as needful coadjutors in the service of God. They, on the other hand, cheerfully declared their willingness to follow in his train, disclaiming any desire to leave him, and engaging to battle with and for him by supplication to God on his behalf. Full of joy at this answer to his request, he unfolded to them his projected line of march; after which he caused a tent of great splendor, representing in shape the figure of a church, to be prepared for his own use in the approaching war. In this he intended to unite with the bishops in offering prayers to the God from whom all victory proceeds.