Most likely Joshua’s age was similar to that of Caleb, around 85 years old (Joshua 14:10). He was one of the original spies who went with Caleb to spy out the land (see Numbers 13:1–33). According to Joshua 13:2, Joshua’s age seems to be a reason for the fighting to be brought to an end. However, given the fact that Caleb is still eager to fight (Joshua 14:11–12) and Moses continued to serve the Lord with strength until his death (Deuteronomy 34:7), surely the Lord could have strengthened Joshua in order to continue the war? Therefore, there must be another reason why the fighting had to stop and the land had to be divided. According to Judges 3:1–4, the Lord deliberately left some nations so that the next generation of Israelites would come to know war. The division of the land must take place so that the tribes know which territories are theirs. This is necessary so that they can continue to drive out the rest of the Canaanites.1 Thus, instead of all the tribes coming together under the leadership of one individual, each tribe must now take on the responsibility of driving out Canaanites in its own allotted area.2
1 Now Joshua was old and advanced in years, and the LORD said to him, “You are old and advanced in years, and there remains yet very much land to possess.