Joshua 21:43 - Joseph Benson’s Commentary on the Old and New Testaments

The Lord gave unto Israel all the land He gave them a right to the whole country, and the actual possession of the greatest part of it. He likewise authorized them to subdue and possess the rest, as soon as it should be needful for them, which was when their numbers were increased; and to exercise absolute dominion over all the people remaining in it. All which was exactly conformable to his promise and oath; for the Israelites not being numerous enough to people the whole land at their first coming into it, God never intended to expel all the old inhabitants at once, but by degrees, as we read expressly, Exodus 23:29.