Zosimus, New History 2.29
Zosimus (Greek Ζώσιμος): Early Byzantine, pagan author of a history of the Roman Empire, published in the first quarter of the sixth century CE.
The translation of Zosimus' New History offered here was printed in 1814 by W. Green and T. Chaplin in London, and was probably prepared by J. Davis of the Military Chronicle and Military Classics Office. The translator is anonymous. The text was found at Tertullian.org. The notes were added by Jona Lendering.
[2.29.1] Now that the whole empire had fallen into the hands of Constantine, he no longer concealed his evil disposition and vicious inclinations, but acted as he pleased, without control. He indeed used the ancient worship of his country, though not so much out of honor or veneration as of necessity. Therefore he believed the soothsayers, who were expert in their art, as men who predicted the truth concerning all the great actions which he ever performed. But when he came to Rome, he was filled with pride and arrogance. He resolved to begin his impious actions at home.
[2.29.2] For he put to death his son Crispus, stiled (as I mentioned) caesar, on suspicion of debauching his mother-in-law Fausta, without any regard to the ties of nature. And when his own mother Helen expressed much sorrow for this atrocity, lamenting the young man's death with great bitterness, Constantine under pretence of comforting her, applied a remedy worse than the disease. For causing a bath to be heated to an extraordinary degree, he shut up Fausta in it, and a short time after took her out dead.
[2.29.3] Of which his conscience accusing him, as also of violating his oath, he went to the priests to be purified from his crimes. But they told him that there was no kind of lustration that was sufficient to clear him of such enormities. An Egyptian, arriving from Spain and very familiar with the court-ladies, being at Rome, happened to fall into converse with Constantine, and assured him that the Christian doctrine would teach him how to cleanse himself from all his offences,
[2.29.4] and that they who received it were immediately absolved from all their sins. Constantine had no sooner heard this than he easily believed what was told him, and forsaking the rites of his country, received those which the Egyptian offered him; and for the first instance of his impiety, suspected the truth of divination. For since many fortunate occurrences had been thereby predicted to him, and really had happened according to such prediction, he was afraid that others might be told something which should fall out to his misfortune; and for that reason applied himself to the abolishing of the practice.
[2.29.5] And on a particular festival, when the army was to go up to the Capitol, he very indecently reproached the solemnity, and treading the holy ceremonies, as it were, under his feet, incurred the hatred of the Senate and People.