Life of Constantine

But while Licinius, giving himself up to these impieties, rushed blindly towards the gulf of destruction, the emperor on the other hand, when he saw that he must meet his enemies in a second battle, devoted the intervening time to his Saviour. He pitched the tabernacle of the cross outside and at a distance from his camp, and there passed his time in a pure and holy manner, offering up prayers to God; following thus the example of his ancient prophet, of whom the sacred oracles testify, that he pitched the tabernacle without the camp. He was attended only by a few, whose faith and pious devotion he highly esteemed.

And this custom he continued to observe whenever he meditated an engagement with the enemy. For he was deliberate in his measures, the better to insure safety, and desired in everything to be directed by divine counsel. And making earnest supplications to God, he was always honored after a little with a manifestation of his presence. And then, as if moved by a divine impulse, he would rush from the tabernacle, and suddenly give orders to his army to move at once without delay, and on the instant to draw their swords. On this they would immediately commence the attack, fight vigorously, so as with incredible celerity to secure the victory, and raise trophies of victory over their enemies.