Joshua 8:2-6

You shall do to Ai and its king just as you did to Jericho and its king; you shall take only its spoils and its cattle as plunder for yourselves. Set an ambush for the city behind it.”

So Joshua rose up with all the people of war to go up to Ai; and Joshua chose thirty thousand men, valiant warriors, and sent them out at night.

He commanded them, saying, “See, you are going to ambush the city from behind it. Do not go very far from the city, but all of you be ready.

Then I and all the people who are with me will approach the city. And when they come out to meet us as they did the first time, we will flee before them.

They will come out after us until we have lured them away from the city, for they will say, ‘They are fleeing before us just as they did the first time.’ So we will flee before them.