After these things, Celsus appears to me to act like those who, in their intense hatred of the Christians, maintain, in the presence of those who are utterly ignorant of the Christian faith, that they have actually ascertained that Christians devour the flesh of infants, and give themselves without restraint to sexual intercourse with their women. Now, as these statements have been condemned as falsehoods invented against the Christians, and this admission made by the multitude and those altogether aliens to our faith; so would the following statements of Celsus be found to be calumnies invented against the Christians, where he says that “he has seen in the hands of certain presbyters belonging to our faith barbarous books, containing the names and marvellous doings of demons;” asserting further, that “these presbyters of our faith professed to do no good, but all that was calculated to injure human beings.”
Would, indeed, that all that is said by Celsus against the Christians was of such a nature as to be refuted by the multitude, who have ascertained by experience that such things are untrue, seeing that most of them have lived as neighbours with the Christians, and have not even heard of the existence of any such alleged practices!
Source: Against Celsus (New Advent)