2 Peter 2:17-22 ESV
These are waterless springs and mists driven by a storm. For them the gloom of utter darkness has been reserved.  For, speaking loud boasts of folly, they entice by sensual passions of the flesh those who are barely escaping from those who live in error.  They promise them freedom, but they themselves are slaves of corruption. For whatever overcomes a person, to that he is enslaved.  For if, after they have escaped the defilements of the world through the knowledge of our Lord and Savior Jesus Christ, they are again entangled in them and overcome, the last state has become worse for them than the first.  For it would have been better for them never to have known the way of righteousness than after knowing it to turn back from the holy commandment delivered to them.  What the true proverb says has happened to them: “The dog returns to its own vomit, and the sow, after washing herself, returns to wallow in the mire.”
Peter continues his description of the false prophets of his day.
Firstly, the false teachers make empty promises. "They promise them freedom, but they themselves are slaves of corruption" (v19). They promise to free people, most likely from sin, but they themselves are enslaved to sin. Thus they are "waterless springs" (v17). They appear to be "springs", but when you go to them, there is no water (i.e. freedom). They speak "loud boasts" about things, but it is just foolishness at the end of the day (v18).
This is the way with all of Satan's temptations. The devil's offer appears to be a "spring", but when you go to it, there is no satisfaction, no quenching of thirst – only the exacerbation of it. The Serpent promises us "freedom" (from whatever) but the end is nothing but slavery.
Only Jesus can promise to give us "freedom" from sin, and follow through on His promise, because only He is the human being without sin – the God Man. A slave cannot free another slave. Only a free man can:
John 8:36 ESV
So if the Son sets you free, you will be free indeed.
Secondly, these false teachers used to be professing Christians who committed apostasy because they never had their nature changed.
At least externally, these false teachers appeared to have "escaped the defilements of the world". They also appeared to have a "knowledge" of Jesus. They also have "known the way of righteousness" (v20). They have 'learned' that Jesus is the Right Way. I'm sure they were baptised Christians who attended church and Bible studies regularly.
But, eventually, they were "entangled" in and "overcome" by the "defilements of the world" again (v20). They "turned back from the holy commandment" (v21), which was "Repent and Believe in Jesus!"
Why? Because their nature never changed through regeneration:
2 Peter 2:22 ESV ... “The dog returns to its own vomit, and the sow, after washing herself, returns to wallow in the mire.”
Why did the dog return to its own vomit? Because it's a dog! That's what dogs do! Why did the pig go back in to the mire? Because that's what pigs do! That's where pigs belong – in the mud. If the dog's nature was changed into a man's, it would not have returned to the vomit. Because that's disgusting! If the pig had turned into a human being, it would stayed out of the mud. Why? Because that's not what a human being does.
In the same way, when we are truly born-again to become a child of God, we do not go back to the vomit of our past sins. EVEN IF WE DO (because old habits die hard), we do NOT like it – because our nature has changed, to know how disgusting our sins really were. We don't return to the mire of our sins. Even if we do, we hate it, because we know that we are God's children and that mire is NOT where we belong any more.
Our nature has changed!
Also, the reason why these false teachers went back to their old lifestyle was because they never received Jesus Christ as their PERSONAL Lord and Saviour. Look what it says in v20: "For if, after they have escaped the defilements of the world through the knowledge of OUR Lord and Savior Jesus Christ..."
It does NOT say: "For it, after they escaped the defilements ... through the knowledge of THEIR Lord and Saviour". Jesus was never THEIR personal Lord and Saviour. Jesus was always someone else's Lord and Saviour. They just tried other people's Jesus out for a few years. And they didn't like Him.
Let us make sure that Jesus is not someone else's Lord and Saviour, but that He is MY Lord, who rules over my life, and MY Saviour who died for my sins. Let us 'own' Him as "mine", and we as "His".
- Pray that you will not pay attention to the empty promises of Satan. That you will see that the end of succumbing to his temptation is nothing but endless thirst and slavery.
- If you are a truly born-again Christian, pray that you will 'be who you are'. That you will not go back to the vomit of your past sins, because you now understand how disgusting that is, and that you will not go back to the mire of your old lifestyle, because that's no longer where you belong.
- If you are not born-again, ask God to cause you to be born-again to give you a truly new nature that hates sin and loves righteousness.
- Pray that Jesus will be YOUR personal Lord and Saviour, not somebody else's. That you will fully own Him as yours.