Matthew Henry Commentary Numbers 36:1-4

"And the heads of the fathers` [houses] of the family of the children of Gilead, the son of Machir, the son of Manasseh, of the families of the sons of Joseph, came near, and spake before Moses, and before the princes, the heads of the fathers` [houses] of the children of Israel: and they said, Jehovah commanded my lord to give the land for inheritance by lot to the children of Israel: and my lord was commanded by Jehovah to give the inheritance of Zelophehad our brother unto his daughters. And if they be married to any of the sons of the [other] tribes of the children of Israel, then will their inheritance be taken away from the inheritance of our fathers, and will be added to the inheritance of the tribe whereunto they shall belong: so will it be taken away from the lot of our inheritance. And when the jubilee of the children of Israel shall be, then will their inheritance be added unto the inheritance of the tribe whereunto they shall belong: so will their inheritance be taken away from the inheritance of the tribe of our fathers." — Numbers 36:1-4 (ASV)

The leaders of the tribe of Manasseh pointed out the evil that might follow if the daughters of Zelophehad were to marry into any other tribes. They sought to preserve the divinely appointed system of inheritances and to ensure that disputes and quarrels would not arise among future generations. It is the wisdom and duty of those who have worldly estates to settle their affairs and arrange for the distribution of their property, so that no strife and contention may arise. (Numbers 36:5–12)