Have you tasted of God’s righteousness finding it spiritually delicious?
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. 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. (2 Peter 2:21-22 KJV)
Peter is speaking in this verse about people who are living in a state of apostasy; having tasted of the goodness of God, cashing in on His holiness, grace and mercy by professing to accept His invitation available for all mankind but failing to live in obedience and produce spiritual fruit.
Once man has tasted the Truths of God understanding the simple equation of mankind’s spiritual accountability to God for a debt of sin they could never hope to pay knowing that God in His great goodness and mercy paid the ledger of all sin in full by His finished work on the cross. That he accounted unto whosoever shall accept His gift of rich mercy and grace through faith in God shall know and have the way of righteousness upon this earth and for all eternity to turn away from, choosing to suppress the Truth, is therefore standing upon a foundation of spiritual devastation and quick sand.
For man to turn once again to his own horrid natural condition of sin rejecting the holiness and goodness of God puts man in a position of wallowing in greater mire and wickedness than he ever did before.