9 Augustine replied: Your idea of taking any prophecies of Christ to be found in Moses, as a fish out of the sea, while you throw away the water from which the fish is taken, is a clever one. But since all that Moses wrote is of Christ, or relates to Christ, either as predicting Him by words and actions, or as illustrating His grace and glory, you, with your faith in the untrue and untruthful Christ from the writings of Manichæus, and your unbelief in Moses, will not even eat the fish.
Moreover, though you are sincere in your hostility to Moses, you are hypocritical in your praise of fish. For how can you say that there is no harm in eating a fish taken out of the sea, when your doctrine is that such food is so hurtful, that you would rather starve than make use of it? If all flesh is unclean, as you say it is, and if the wretched life of your god is confined in all water or plants, from which it is liberated by your using them for food, according to your own vile superstition, you must throw away the fish you have praised, and drink the water and eat the thistles you speak of as useless.
As for your comparison of the servant of God to devils, as if his prophecies of Christ resembled their confession, the servant does not refuse to bear the reproach of his master. If the Master of the house was called Beelzebub, how much more they of His household! You have learned this reproach from Christ's enemies; and you are worse than they were. They did not believe that Jesus was Christ, and therefore thought Him an impostor. But the only doctrine you believe in is that which dares to make Christ a liar.
Source: Reply to Faustus the Manichaean (New Advent)