The occasion for this law was a representation made to Moses and the princes of the congregation by the heads of the fathers' houses (האבות for בּית־האבות, as in Exodus 6:25, etc.) of the family of Gilead the Manassite, to which Zelophehad (Numbers 26:33) belonged, to the effect that, by allotting an hereditary possession to the daughters of Zelophehad, the tribe-territory assigned to the Manassites would be diminished if they should marry into another tribe. They founded their appeal upon the command of Jehovah, that the land was to be distributed by lot among the Israelites for an inheritance (Numbers 36:2 compared with Numbers 26:55-56, and Numbers 33:54); and although it is not expressly stated, yet on the ground of the promise of the everlasting possession of Canaan (Genesis 17:8), and the provision made by the law, that an inheritance was not to be alienated (Leviticus 25:10, Leviticus 25:13, Leviticus 25:23.), they understood it as signifying that the portion assigned to each tribe was to continue unchanged to all generations. (The singular pronoun, my Lord, in Numbers 36:2, refers to the speaker, as in Numbers 32:27.) Now, as the inheritance of their brother, i.e., their tribe-mate Zelophehad, had been given to his daughters (Numbers 27:1), if they should be chosen as wives by any of the children of the (other) tribes of Israel, i.e., should marry into another tribe, their inheritance would be taken away from the tribe-territory of Manasseh, and would be added to that of the tribe into which they were received. The suffix להם (Numbers 36:3) refers ad sensum to מטּה, the tribe regarded according to its members.

Numbers 36:8 Parallel Commentaries

every daughter

1 Chronicles 23:22 And Eleazar died, and had no sons, but daughters: and their brothers the sons of Kish took them.