Against Celsus 8.36

But the angels of God, who are truly his satraps, governors, generals, and procurators, do not, as Celsus thinks, harm those who insult them; and if some demons, such as Celsus too imagined, do harm, they harm as wicked beings who have been entrusted with no satrapy, command, or stewardship from God, and they harm those subject to them who have submitted to them as masters. For perhaps this is why those who in each place transgress in eating the foods customarily considered forbidden are harmed, if they are among those under those demons; whereas if some are not under them and have not subjected themselves to the demon of the place, they are free from suffering anything at their hands, though, having bidden farewell to such demons but subjected themselves to others through ignorance of other things, they may suffer at their hands. But the Christian, the true Christian, who has subjected himself to God alone and to his Word, would suffer nothing from the demons, since he is stronger than demons. And he would suffer nothing, since “the angel of the Lord will encamp around those who fear him and will deliver them,” and his angel, who “always” beholds “the face of the Father” “in heaven,” always carries up his prayers through the only high priest to the God of the universe, and himself prays together with the one entrusted to his care. Let Celsus, then, not frighten us like children with bogeys, threatening the harm that comes from the demons if we neglect them; for demons, though neglected, could do nothing to us, who are devoted to him who alone can help all who are worthy, and who none the less sets his own angels over those who worship him, so that neither the opposing angels nor the one called their “ruler of this age” may be able to work anything against those devoted to God.