Numbers 26:53-56

(53-56) Unto these the land shall be divided... — The general apportionment of the land, as regarded the relative position of each tribe, was to be decided by lot, which was commonly looked upon as the determination of God Himself, and in this instance was undoubtedly so. The extent of territory was to be determined by the number of names — i.e., of persons — in each tribe, and each inheritance was to bear the name of the ancestor of the tribe. Rashi says that the names of the twelve tribes were written on twelve scrolls of parchment, and twelve borders, or limits of land, on twelve others, and that they were mixed together in an urn.