And the pig, because it parts the hoof and is cloven-footed but does not chew the cud, is unclean to you.
Now that Aaron was consecrated a high priest over the house of God, God spoke to him with Moses, and appointed them both as joint-commissioners to deliver his will to the people. He spoke both to Moses and to Aaron about this matter; for it was particularly required of the priests that they should put a difference between clean and unclean, and teach the people to do so.
Commenting on Leviticus 11:1-8
And the swine, though he divide the hoof, and be cloven footed,.... Not only its hoofs are parted, but cloven quite through, and so in this respect answers Moses's first descriptive character of clean creatures; though Aristotle (u) and Pliny (w) speak of some kind of swine in Illyricum, Paeonia, and other places, which have solid hoofs; but perhaps these were not properly swine, though...
the swine--It is a filthy, foul-feeding animal, and it lacks one of the natural provisions for purifying the system, "it cheweth not the cud"; in hot climates indulgence in swine's flesh is particularly liable to produce leprosy, scurvy, and various cutaneous eruptions. It was therefore strictly avoided by the Israelites. Its prohibition was further necessary to prevent their adopting many of the grossest idolatries practised by neighboring nations.