For they did not gain possession of the land by their own sword, nor did their own arm save them; but it was Your right hand, Your arm, and the light of Your countenance, because You favored them.
When God led the children of Israel out of Egypt, He had Moses explain to the people: “The LORD will fight for you, and you shall hold your peace” (Exodus 14:14). First God wiped out the mighty Egyptian army without the Israelites even using a sword (Exodus 14:23-28). And then He promised the Israelites that He would “drive out the Canaanite” before them (Exodus 33:2).
When the Israelites rebelled, God allowed them to fight some of their own battles. But, as He showed by making the walls of Jericho fall (Joshua 6:20), it was really His miraculous intervention that allowed them to gain the Promised Land. Without God’s help, they would not have been able to take the land.
For more about why God allowed His people to fight, see “War in the Bible: Why Did God’s People Go to War?”