Joshua 13 opens with these words: “Now Joshua was old and advanced in years”. That makes me tired just thinking about it. Joshua has been extremely busy leading the people since he took over for Moses. It doesn’t seem like that long, although a lot of water has gone under the bridge. He has conquered 31 kings to date, but God says “there remains yet very much land to possess”. The job is far from complete. Lots more kings and kingdoms to overtake to complete the move into the Promised Land.
Scripture lists those kings and kingdoms and also gives the answer to Joshua’s old age and limitations. “I myself will drive them out from before the people of Israel”. God knows no limitations. His man on the ground was old and tired, so God says He will just do it Himself. He isn’t limited by our limitations as people. He has demonstrated that over and over with the plagues, and more recently the hailstones He used as weapons to wipe out a bunch of the enemy. God has the tools to make it happen – whether Joshua is able to be part of it or not.
The balance of the chapter is a detailed description of the land to be taken, as well as what has already been taken, and how that should be carved up among the 12 tribes. It actually is only going to 11 tribes as the Levites were “gave no inheritance”. They were the keepers of God’s things and were not going to be owners of any property. But the rest of the tribes have specific areas that are to be their own. Some still had enemies that needed to be removed, some have been living in their new homeland for a while. But God is on a steady march to provide the land He promised. Joshua is still leading the way, although it may be slowing down a bit with his age!
Arlin Sorensen's Thoughts on Scripture 