Numbers 33:50-55

Then the LORD spoke to Moses in the plains of Moab by the Jordan across from Jericho, saying, “Say to the children of Israel, ‘When you cross the Jordan into the land of Canaan, then you shall drive out all the inhabitants of the land before you and destroy all their sculpted images, and destroy all their cast idols and completely eliminate all their [idolatrous] high places, and you shall take possession of the land and live in it, for I have given the land to you to possess. You shall inherit the land by lot according to your families; to the large tribe you shall give a larger inheritance, and to the small tribe you shall give a smaller inheritance. Wherever the lot falls to any man, that shall be [the location of] his [inheritance]. According to the tribes of your fathers (ancestors) you shall inherit. But if you do not drive out the inhabitants of the land from before you, then those you let remain of them will be like pricks in your eyes and like thorns in your sides, and they will attack you in the land in which you live.