Against Celsus 8.29

We must know, however, that while the Jews thought they understood the law of Moses, and observed in the matter of foods that they should partake of those considered clean by them and abstain from the unclean, and also not use the blood of an animal as food, nor what was caught by wild beasts, and other things about which there is much to say and which it is therefore not the time to examine now, the teaching of Jesus, wishing to call all men to pure worship of God, and not to hinder, on the pretext of heavier legislation about foods, many who could be helped in their conduct by Christianity, declared that “it is not what goes into the mouth that defiles a man, but what comes out of the mouth”; for “what goes into the mouth,” he says, “passes into the stomach and is expelled into the drain,” while what comes out of the mouth is “evil thoughts” spoken, and “murders,” “adulteries,” “sexual immorality,” “thefts,” “false witness,” and “blasphemies.” And Paul too says that “food will not commend us to God; for we are no better off if we eat, and no worse off if we do not eat.” Then, since these things have some unclearness unless they are explained, “it seemed good to the apostles” of Jesus “and to the presbyters” gathered together at Antioch, and, as they themselves put it, “to the Holy Spirit,” to write a letter to believers from the Gentiles, forbidding them to eat only what they called “necessary things”: that is, food offered to idols, what is strangled, and blood.