It’s well known that Jewish law forbids simmering a kid in its mother’s milk. That’s the textual basis of what became in Rabbinic times the sweeping rules requiring the complete separation of milk and meat.
What’s less clear is:
(1) Why anyone would want to simmer a kid in its mother’s milk; and
(2) Why anyone should care.
It’s especially puzzling because the rule forms part of the second list of the Ten Commandments (given in Ex. 34: 14-28). The text says that the second list - given after Moses had broken the original tablets in outrage over the Golden Calf incident - is the same as the first list (Ex. 20:2-14.) Both are referred to as the Ten Words ( ×“Ö¼Ö°×‘Ö¸×¨Ö´×™× , devarim). But that isn’t the case. Here’s the later, less familiar list:
1. Thou shalt bow down to no other god; for the LORD, whose name is Jealous*, is a jealous God;Â lest thou make a covenant with the inhabitants of the land, and they go astray after their gods, and do sacrifice unto their gods, and they call thee, and thou eat of their sacrifice;Â and thou take of their daughters unto thy sons, and their daughters go astray after their gods, and make thy sons go astray after their gods.
2. Thou shalt make thee no molten gods.
3. Â The feast of unleavened bread shalt thou keep. Seven days thou shalt eat unleavened bread, as I commanded thee, at the time appointed in the month Abib, for in the month Abib thou camest out from Egypt.
4.  All that openeth the womb is Mine; and of all thy cattle thou shalt sanctify the males, the firstlings of ox and sheep. And the firstling of an ass thou shalt redeem with a lamb; and if thou wilt not redeem it, then thou shalt break its neck. All the first-born of thy sons thou shalt redeem. None shall appear before Me empty.
5. Six days thou shalt work, but on the seventh day thou shalt rest; in plowing time and in harvest thou shalt rest.
6. Â And thou shalt observe the feast of weeks, even of the first-fruits of wheat harvest, and the feast of ingathering at the turn of the year.
7.  Three times in the year shall all thy males appear before the Lord GOD, the God of Israel.  For I will cast out nations before thee, and enlarge thy borders; neither shall any man covet thy land, when thou goest up to appear before the LORD thy God three times in the year.
8. Thou shalt not offer the blood of My sacrifice with leavened bread; neither shall the sacrifice of the feast of the passover be left unto the morning.
9. The choicest first-fruits of thy land thou shalt bring unto the house of the LORD thy God.
10. Thou shalt not seethe a kid in its mother’s milk.
So the rule about the kid isn’t just on the list of ten, it’s the climax of the list. Admittedly, it’s a pretty miscellaneous set of rules, much less coherent - to a modern eye - than the more familiar Ten Commandments. There’s not much on it that looks like a general ethical precept, as opposed to cultic practice. But how does making a Stroganoff get up there with idolatry on the list of no-nos?
When we discussed this passage at the Hirshleifer-Rosett UCLA Faculty Tanakh Study Group (I’m no longer the note-taker, but I still attend when I can), Paula Powers Coe, a folklorist of awesome learning, had the answer.
It turns out that a kid simmered in its mother’s milk was the sacrifice offered to Ishtar.
So the last item on the list gets back to the first: not adopting the religious practices of the neighbors. Thou shalt not attend the National Prayer Breakfast!
* Apparently “jealous” isn’t accurate; the word ×§Ö·× Ö¼Ö¸× has to do with accounting, and “persnickety” or “detail-oriented” would be a better translation.