v1: The solid basis of chapter 1 prepares the readers for the false teachers and various errors exposed in this chapter.

"Among" the people; error had come in, and would come in; Acts 20.29. Peter looked back to false prophets who had influenced Israel, and he looked forward to false teachers among the church of Christ.

They came in secretly, so we need to be watchful. They brought heresies, which are destructive. They denied the Lord Jesus, so we must be clear in our teaching about Him. They denied the Lord who 'bought them,' minimiisng the crucifixion and resurrection. True teaching emphasizes those central truths (1 Cor 15.3-4).

This is the ultimate test of Christian orthodoxy, 1 John 4.3. Such teachers damage others, and will bring destruction on themselves.

v2: Many will follow the ways of false teachers, see 1 Cor 11.19; the identification of false teachers and false brethren shows those who are "approved." The false teachers bring the way of truth into disrepute; our lives should bring honour to the message of Christ.

v3: Greedy, exploitative, deceitful; characteristics of these people. We must be careful of them. Peter makes no reference to agents of Satan, which would make us look for something overtly awful; rather we must be discerning, and be faithful in teaching the truth.

v4-10: Lessons from the past; the Lord delivered Noah through the flood, and Lot from Sodom and Gomorrah; He knows how to deliver the godly. These verses are an encouragement for us.

v4: Reference to the angels who rebelled with Satan, Jude 6. The Lord Jesus spoke of the place prepared for he devil and his angels.

v5: God brought Noah through the flood. He had been a preacher of righteousness, and doubtless warned the people, yet none followed him except his own family.

v6: God turned the cities of Sodom and Gomorrah into ashes.

These things are a warning and example of what will happen to the ungodly. God punished deliberate, persistent rebellion. Here is a warning to any who think they can dismiss God's words as empty threats.

v7: Although Lot was not perfect, and made a number of errors, God described him as godly. God therefore delivered him.

This is an encouragement for us, since God's protection of us is not dependent upon our spiritual progress, but simply upon the fact that we belong to Him.

v8: The Lord knew Lot's circumstances, and showed mercy to him, even though he was foolish to live in Sodom. The Lord remained faithful, and He cannot deny Himself, and He cared for him. He knows the circumstances in which we live and serve.

Although Lot made some unwise decisions, he is here referred to as 'righteous.' We do not judge those who make different choices to us.

v9: The Lord knows those who are His, and will rescue them. Such are called "godly" for we ought to be godly.

The Lord makes a distinction with those who are unrighteous, who will suffer punishment. There is a coming day of judgment, before which they are "kept in darkness" (Jude 6). We have confidence in the Lord; He continues to rescue the godly; those who belong to Him.

v10: The unjust include those who follow corrupt desires and who despise authority. This authority is pre-eminently Jesus Christ, but will also include church leadership.

v10-11: Peter has indicated that God can distinguish true from false. He now further describes those who bring false teaching. Compare Jude 8-9; they are presumptuous, self-willed, despising authorities.

v12: Compare Jude 10; they are untamed and uncontrolled. They despise the truth which they do not understand. They will perish in their own corruption.

Peter's words here are strong, but we must realise the seriousness of the effects that these men could have upon the church of Christ.

v13: They will receive their wages, their just desserts. They are covetous, loving the "wags of wickedness" (v15). They are loves or pleasure, hedonistic, without restraint.

They are "blots and blemishes" (contrast Eph 5.27) which mar the true church; yet they "feast with you" having secretly infiltrated individual church groups. The shocking truth is that such people were seen as Christians.

v14: They remained under the control of sin, compare Heb 6.4-6. They were experts, not in godliness, but in covetousness. Even so, they had a measure of 'success' in beguiling unstable souls, gaining disciples for themselves. Should we not care more for the "unstable"? Some Christians are more vulnerable than others.

v15: Balaam is the example of greed. This is something dangerous, which has led many astray. We must be careful of the influence of money.

v16: God used a dumb donkey to rebuke the prophet, rebuking and humbling him. The prophet was mad, just like the false teachers.

God uses many means, although His character remains the same.

v17: Springs without water, offering much, but delivering little.

v18: They speak eloquently and convincingly, no wonder others are led astray. Again we notice that some followed who had already escaped falsehood; the false teachers bring them back into bondage, Matt 23.13,15; Gal 2.4.

To the observer, the church is somewhat messy, with different things being said, true and false mixed; yet the Lord Jesus spoke of the weeds and tares growing together.

v19: They promise liberty, but cannot deliver, for they themselves are in bondage. In context there were religious people from a Jewish background. But we cannot restrict false teachers to that description. These warnings are relevant, and we must take notice.

v20-22: The dangers of being led astray, Heb 6.4-6. It seems that they were not true Christians; they had tasted the things of Christ, had known the way of righteousness, had some change of behaviour or attitude; they are worse off as they return to the pollution of the world. As in Luke 11.24-26, their final state was worse than their first.