Testimonium — Apelles the Marcionite: one principle, the prophetess Philumene; Rhodo's debate with him (Rhodo, via Eusebius, Church History 5.13)
Therefore also they disagree among themselves, maintaining an inconsistent opinion. For Apelles, one of the herd, priding himself on his manner of life and his age, acknowledges one principle, but says that the prophecies are from an opposing spirit, being led to this view by the responses of a maiden by name Philumene, who was possessed by a demon.
5. The same author writes that he engaged in conversation with Apelles. He speaks as follows:
For the old man Apelles, when conversing with us, was refuted in many things which he spoke falsely; whence also he said that it was not at all necessary to examine one's doctrine, but that each one should continue to hold what he believed. For he asserted that those who trusted in the Crucified would be saved, if only they were found doing good works. But as we have said before, his opinion concerning God was the most obscure of all. For he spoke of one principle, as also our doctrine does.
9. But this Apelles wrote many things, in an impious manner, of the law of Moses, blaspheming the divine words in many of his works, being, as it seemed, very zealous for their refutation and overthrow.