2 Peter 2:20-22

V.20. For if, after they have escaped the pollutions of the world through the knowledge of the Lord and Savior Jesus Christ, they are again entangled therein and overcome, the latter end is worse with them than the beginning. V.21. For it had been better for them not to have known the way of righteousness than, after they have known it, to turn from the holy commandment delivered unto them. V.22. But it is happened unto them according to the true proverb, The dog is turned to his own vomit again; and the sow that was washed, to her wallowing in the mire.

The consequences of false teachers' behavior are brought out in a striking manner by St. Peter:

For if, after having escaped the pollutions of the world in the knowledge of our Lord and Savior Jesus Christ, they are again taken captive and vanquished by these, their latter state is worse than the first.

The men whom the apostle had in mind had probably been converted to Christ in all good faith. They had fled from the pollutions, the profanations, the sins of the world, and taken refuge in the redemption of Christ. Having learned to know Jesus Christ as their Lord and Savior, they had truly abhorred their former sinful life. It is for this reason that the apostle speaks such solemn words of warning.

For if a person has had the sound, saving knowledge of Jesus the Savior, if he has chosen Jesus as his Lord, and then deliberately turns back to his former lusts, permits himself to be governed by the sinful desires which he knows to be wrong, then, indeed, his spiritual state after such defection is worse than it was before his conversion, Matt. 12, 45.

Note that the false teachers are described as belonging to the truly converted Christians, to the Christian congregation. It is the false teachers that have fallen away from the truth which they formerly confessed that are the most dangerous, the most hostile to the truth.

Therefore St. Peter rightly says of them: For better it would have been for them not to have known the way of righteousness than to know it and yet to turn from the holy commandment committed to them.

The people that never hear anything of the way of salvation, that have never heeded the voice which bids them search for the true God, Acts 14, 17; 17, 27, will indeed receive stripes, Luke 12, 48.

But he that has become acquainted with the way of righteousness, that knows the way of salvation, and then deliberately spurns the will of God and refuses to be obedient to the Gospel-message, will be in greater condemnation and will be subject to a worse fate, Luke 12, 47.

In the case of such people, as St. Peter writes with some show of irony: It happened to them according to the true proverb, The dog turns back to his own vomit; and the sow, having been washed, to her wallowing in the mire. Compare Proverbs 2 6, 11.

As a dog will eat what he himself has just vomited, as swine delight in wallowing in the deepest filth, even though they have just been washed, so people such as have just been described will leave the purity and the glory and the salvation of the Gospel-message and of a life of sanctification and return to the filth of a life of sin and shame. What a stern warning to all Christians not to sell their immortal souls for a few bits of dross, not to abandon themselves to the sins which they have so freely renounced!

Summary. In warning against the false teachers of all times, the apostle depicts them and their punishment, substantiating his statements by examples taken from Old Testament history; he characterizes them as followers of Balaam and describes the curse of their spiritual slavery.