As he has hitherto referred to the injury they did by the example of a perverse and corrupt life, so he again repeats, that they spread by their teaching the deadly poison of impiety, in order that they might destroy the simple. He compares them to Balaam, the son of Bozor, who employed a venal tongue to curse God’s people. And to shew that they were not worthy of a long refutation, he says that Balaam was reproved by an ass, and that thus his madness was condemned. But by this means also he restrains the faithful from associating with them. For it was a dreadful judgment of God, that the angel made himself known to the ass before he did to the prophet, so that the ass, perceiving God displeased, dared not to advance farther, but went back, when the prophet, under the blind impulse of his own avarice, pushed forward against the evident prohibition of the Lord. For what was afterwards answered to him, that he was to proceed, was an evidence of God's indignation rather than a permission. In short, as the greatest indignity to him, the mouth of the ass was opened, that he who had been unwilling to submit to God's authority might have that as his teacher. And by this miracle the Lord designed to shew how monstrous a thing it was to change the truth to a lie.