Deuteronomy 21

Perhaps to decide which town has jurisdiction in the case and will conduct the investigation.

This doesn’t seem to refer to local Canaanite women, but to women in neighboring nations outside the tribal boundaries of Israel (20:10-15). Moses ordered Israelites to kill all the locals they caught, including all the good-looking women (20:16-18).

There’s no explanation for why women had to shave their heads and trim their nails. Perhaps it was part of the mourning custom or to graphically signify that everything in the woman’s life is about to change, from the hair on her head to the clothes she wears. As for trimming the nails, there might be some mysterious spiritual or ceremonial reason for this. But from a practical point of view, you wouldn’t want long nails on a woman you intended on sleeping with 30 days after you killed her family.

This was a custom throughout what is now the Middle East. It shows up in ancient law codes. Some say the reason may have been because the oldest son was expected to become head of the extended family after the father died. And the extra assets helped him cover the cost of that job. Whatever the reason, it seems unlikely that the lawmaker would have been the second, third, fourth, or fifth son in a family of five sons. What’s odd about the law is that when it’s first mentioned in the Bible, in the story of Ishmael and Isaac (Genesis 17:15-22; 21:8-14) and then again with Esau and Jacob (Genesis 27; 48), the first son doesn’t get the double share. Ishmael and his mother got run off. And Jacob traded Esau a bowl of red soup for Esau’s inheritance rights. So there seems to have been wiggle room in the ancient custom, though Jews may have followed the custom more faithfully since it was added to their laws.

Exodus 20:12.

The Hebrew word for “hang” is tala. It can mean to impale, hang, or expose.

The Hebrew word is es. It can refer to many kinds of wood: tree, pole, beam, or branches. Hanging a body like this was usually intended to send a warning to others not to make the same mistake this person did. Paul said Jesus became cured when he hung on the cross (Galatians 3:13).