Joshua 21:44
And the LORD gave them rest round about, according to all that he sware unto their fathers: and there stood not a man of all their enemies before them; the LORD delivered all their enemies into their hand. And the LORD gave them rest round about, according to all that he sware unto their fathers: and there stood not a man of all their enemies before them; the LORD delivered all their enemies into their hand.
The Lord faithfully fulfilled all He had sworn to the fathers, giving Israel the land of Canaan for a home and rest round about from their enemies. He broke the power of the Canaanites and delivered all their enemies into their hand, so that not a man of them could stand before them.
Taking and holding possession of the land required Israel to trust His aid and obey His commands. His own law was to be the law of the land in which they dwelt in rest.
Satan was determined to keep his hold on Canaan and regarded Israel with cruel and malignant hatred. He plotted their destruction and worked through evil spirits to bring strange gods in among them.
Israel's failure to finish driving out the inhabitants did not arise from any failure of God's promise. It was through their own transgression that they were finally scattered from the land of promise.