So no inheritance shall be transferred from one tribe to another, for each of the tribes of the people of Israel shall hold on to its own inheritance.
The perpetuity of the inheritance in the Promised Land by tribe was prescribed in the Law by Moses. Why? Because the land was God’s blessing. It was home, family farm, and livelihood. And God did not want the nation to become a patchwork quilt of cross-tribal holdings. Keeping land within tribes assured that disputes over what was an important and vital possession would be minimal.
God cared enough for how Israel handled possessions and income that He prescribed common sense regulations to minimize property disputes. He knows that as human beings we get caught up in the stuff we have.
There is also a wonderful picture of the importance of family in this last chapter of Numbers. The daughters of Zelophahad were promised a share of their father’s allotment as long as they married within their father’s tribe. A sonless family could still carry on a legacy and keep its inheritance. This was something unheard of at that time. It speaks to the family’s crucial and indispensible role in society. And it was designed by God to promote continuity in families that obeyed Him throughout generations.