Charles Ellicott Commentary Deuteronomy 14:21

"Ye shall not eat of anything that dieth of itself: thou mayest give it unto the sojourner that is within thy gates, that he may eat it; or thou mayest sell it unto a foreigner: for thou art a holy people unto Jehovah thy God. Thou shalt not boil a kid in its mother`s milk." — Deuteronomy 14:21 (ASV)

That he may eat it. —Literally, and he will eat it. The common practice, and not the intention of the writer, may be indicated. It should be remembered that these rules and restrictions were intended to raise the Israelites above the common level, not to degrade the other nations in comparison with them. Strangers were not compelled to eat what Israel refused; they were left free to please themselves.

You shall not seethe a kid in his mother’s milk. —This is the last appearance of a command repeated twice in Exodus (Exodus 23:19; Exodus 34:26). See Notes there.