Deuteronomy 21

15–17 Having more than one wife at the same time (polygamy) was common in ancient times, though never approved of in Scripture. However, the right of the firstborn was to be determined by order of birth and not by the father’s preference of one wife over another.⁵⁶ The right of the firstborn included receiving a double share of the father’s estate (verse 17). The firstborn son was the first sign of his father’s procreative strength, and the privilege of being firstborn was not to be taken from him.

A Rebellious Son (21:18–21)

18–21 See Leviticus 20:9 and comment.

The Burial of an Executed Criminal (21:22–23)

22–23 The body of an executed criminal was customarily hung on a tree⁵⁷ or impaled on a post in order to serve as a warning to others. However, by nighttime the body had to be buried. Otherwise, prolonged exposure of a dead body would desecrate (defile) the land.

. . . anyone who is hung on a tree is under God’s curse (verse 23). In the context of these verses, anyone who deserved to be executed was guilty of a terrible offense against God and thus came under God’s “curse” or judgment. Hanging a condemned criminal “on a tree” added shame and humiliation to his punishment. Paul quoted verse 23 to show what awful shame and humiliation Christ endured on the cross—even though He died there not for His own sin but for the sins of others (Galatians 3:13).