Numbers 36:6-8

Douay-Rheims 1899 American Edition

⁶ And this is the law promulgated by the Lord touching the daughters of Salphaad: Let them marry to whom they will, only so that it be to men of their own tribe.

⁷ Lest the possession of the children of Israel be mingled from tribe to tribe. For all men shall marry wives of their own tribe and kindred:

⁸ And all women shall take husbands of the same tribe: that the inheritance may remain in the families,