Joshua 8:18
And the LORD said unto Joshua, Stretch out the spear that is in thy hand toward Ai; for I will give it into thine hand. And Joshua stretched out the spear that he had in his hand toward the city. And the LORD said unto Joshua, Stretch out the spear that is in thy hand toward Ai; for I will give it into thine hand. And Joshua stretched out the spear that he had in his hand toward the city.
The command belongs to the conquest of Ai, one of the victories Israel marched out to win from Gilgal, its first encampment in the promised land. It ordered a second advance against Ai after the execution of Achan had turned God's wrath away from Israel. God directed Joshua to point the spear in his hand toward Ai as the signal for attack, with the promise to give the city into his hand. Joshua obeyed, and Israel soon took the city.
The verse called Joshua to marshal all the men of war and go up against Ai again, with the armies of heaven fighting for Israel so that their enemies were put to flight. It shows that Israel's only hope was obedience to God, and that such obedience brought God's mighty working, fresh courage with every victory, and renewed vigor in the conquest until the whole land was taken.