Why did God plan to drive out the tribes living in Canaan?
God planned to drive out the Canaanite tribes inhabiting Canaan so that Abraham's offspring could take possession of the land. This was according to what God had told Abraham, ensuring Israel could occupy the whole area of Canaan as His covenant people, thus fulfilling His promise.
Les teaches that God had told Abraham the Canaanite tribes would be driven out so that His offspring could have the land of Canaan. The area was still inhabited by the Canaanites and various tribes, and God was preparing to lead Israel through Joshua to occupy the whole area. This plan was part of God proving Joshua as His chosen leader, and it involved supernatural acts like crossing the Jordan on dry ground. Les notes that when God deals with Israel, the supernatural is commonplace.