But I have a few things against you, because you have there them that hold the doctrine of Balaam, who taught Balak to cast a stumbling block before the children of Israel, to eat things sacrificed unto idols, and to commit fornication.
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Irenaeus of Lyons
For, speaking no longer by the Spirit of God, but setting up another law of fornication contrary to the law of God,
That is, I will say what I shall command, and I will tell you what you shall do. For Balaam, with his doctrine, taught Balak to cast a stumbling-block before the eyes of the children of Israel, to eat what was sacrificed to idols, and to commit fornication—a thing which is known to have happened of old. For he gave this advice to the king of the Moabites, and they caused stumbling to the people. Thus, says He, you have among you those who hold such doctrine; and under the pretext of mercy, you would corrupt others.