“A dog returns to its vomit”
Of them the proverbs are true: 'A dog returns to its vomit,' and, 'A sow that is washed goes back to her wallowing in the mud.' (2 Peter 2:22 BSB)
What it sounds like today
A pair of crude, memorable insults.
The cultural key
Peter stacks two earthy proverbs to describe those who briefly embrace the faith and then revert. The first, 'a dog returns to its vomit,' quotes Proverbs 26:11 directly. The second, the washed sow returning to the mud, is a folk saying paralleled in ancient Near Eastern wisdom such as the Story of Ahikar. Both animals, dog and pig, were unclean, sharpening the insult, and both proverbs make the same point: a wash on the outside changes nothing if the nature underneath is unchanged. The sow enjoys being clean for a moment, then heads straight back to the mire.
Recovered meaning
A surface reformation that leaves the heart untouched does not last; the creature returns to what it truly is. Peter's blunt proverbs warn that outward cleansing without inward change is no salvation at all.