The Ecclesiastical History of Sozomen

After this reverse, Licinius, who had previously respected the Christians, changed his opinion, and ill-treated many of the priests who lived under his government; he also persecuted a multitude of other persons, but especially the soldiers. He was deeply incensed against the Christians on account of his disagreement with Constantine, and thought to wound him by their sufferings for religion, and besides, he suspected that the churches were praying and zealous that Constantine alone should enjoy the sovereign rule. In addition to all this, when on the eve of another battle with Constantine, Licinius, as was wont to be done, made a forecast of the expected war, by sacrifices and oracles, and, deceived by promises of conquest, he returned to the religion of the pagans.

The pagans themselves, too, relate that about this period he consulted the oracle of Apollo Didymus at Miletus, and received an answer concerning the result of the war from the demon, couched in the following verses of Homer:

“Much, old man, do the youths distress thee, warring against thee!

Feeble thy strength has become, but thy old age yet shall be hardy.”

From many facts it has often appeared to me that the teaching of the Christians is supported, and its advancement secured, by the providence of God; and not least from what then occurred; for at the very moment that Licinius was about to persecute all the churches under him, the war in Bithynia broke out, which ended in a war between him and Constantine, and in which Constantine was so strengthened by Divine assistance that he was victorious over his enemies by land and by sea. On the destruction of his fleet and army, Licinius threw himself into Nicomedia, and resided for some time at Thessalonica as a private individual, and was eventually killed there. Such was the end of one who, at the beginning of his reign, had distinguished himself in war and in peace, and who had been honored by receiving the sister of Constantine in marriage.