2 Peter 2:22

It has happened unto them according to the old proverb, The dog having returned to his own vomit; and the sow that had washed to wallowing in the mire.

Treasury of Scripture Knowledge

Summary

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.

Bible References

General references

Matthew 7:27
And the rain came down, and the rivers came, and the winds blew, and beat against that house; and it fell: and great was the fall of it.
Luke 14:30
saying, that this man began to build, and was not able to complete it.
Luke 17:32
Remember Lot's wife.
1 Timothy 5:15
for already certain ones have turned away after Satan.