22. But it has happened unto them. As the example disturbs many, when men who had submitted to the obedience of Christ, rush headlong into vices without fear or shame, the Apostle, in order to remove the offense, says that this happens through their own fault, and that because they are pigs and dogs. It hence follows that no part of the sin can be ascribed to the gospel.
For this purpose he quotes two ancient proverbs, the first of which is found as the saying of Solomon in Proverbs 26:11. But what Peter meant is briefly this, that the gospel is a medicine which purges us by wholesome vomiting, but that there are many dogs who swallow again what they have vomited to their own ruin; and that the gospel is also a laver which cleanses all our uncleanness, but that there are many swine who, immediately after washing, roll themselves again in the mud. At the same time the godly are reminded to take heed to themselves, except they wish to be deemed dogs or swine.