Luke 15:15-16

And he went and joined himself to a citizen of that country; and he sent him into his fields, to feed swine.

2 Peter 2:22

But it has befallen them according to the true proverb, The dog is turned to his own vomit, and the sow that was washed to her wallowing in the mire.

Treasury of Scripture Knowledge

Summary

And the swine, because it divideth the hoof, yet cheweth not the cud, it is unclean unto you: ye shall not eat of their flesh, nor touch their dead carcase.

Bible References

The swine

Luke 15:15
And he went and joined himself to a citizen of that country; and he sent him into his fields, to feed swine.
2 Peter 2:22
But it has befallen them according to the true proverb, The dog is turned to his own vomit, and the sow that was washed to her wallowing in the mire.