Church History, Book 3
The Campaign Against the Persians
As soon as the Persians heard of the death of Constantius, they took heart, declared war, and marched across the frontier of the Roman Empire. So Julian decided to muster his forces, though they were an army with no God to guard them. First he sent to Delphi, to Delos, to Dodona and to the other oracles, and asked the seers whether he should march. They told him to march and promised him victory. I add one of these oracles here as proof of their falsehood. It ran like this: “Now all we gods have set out to win trophies of victory by the river Beast, and I, Ares, the bold raiser of the din of war, will be their leader.” Let those who call the Pythian god wise in speech and leader of the Muses laugh at the absurdity of this answer. I, who have found out its falsehood, will rather pity the man who was cheated by it. The oracle called the Tigris “Beast” because the river and the animal have the same name. The river rises in the mountains of Armenia, flows through Assyria, and empties into the Persian Gulf.
Led on by these oracles, the unhappy man indulged in dreams of victory, and pictured himself, after fighting the Persians, making war on the Galileans; for that is what he called the Christians, thinking that in this way he would bring them into disgrace. But educated man that he was, he ought to have reflected that a change of name does no harm to a reputation. Even if Socrates had been called Critias, and Pythagoras Phalaris, they would have suffered no disgrace from the change of name; nor would Nireus, if he had been named Thersites, have lost the good looks nature gave him. Julian had learned about these things, but took none of them to heart, and supposed that he could wrong us by using an unfitting name. He believed the lies of the oracles, and threatened to set up the statue of the goddess of lust in our churches.