Verse 19.— While they promise them liberty. The promise held out to those sought to be apostatized and drawn from the faith was liberty. This was the promise. Liberty in this, that men possessing appetites are, and of right ought to be, free to indulge them without restraint. These teachers claimed that restraint in this regard was bondage. Those enduring this restraint would be relieved therefrom by following the advice of these teachers. This Promise is made by those who are the veriest slaves. They are under bondage to corruption, which is an implacable tyrant. For of whom a man is overcome. This is a legitimate and necessary conclusion. So says the apostle Paul. "His servants ye are to whom you obey, whether of sin unto death, or of obedience unto righteous­ness" (Romans 6:16).