Joshua 8:2-4

New Revised Standard Version Catholic Edition

² You shall do to Ai and its king as you did to Jericho and its king; only its spoil and its livestock you may take as booty for yourselves. Set an ambush against the city, behind it.”

³ So Joshua and all the fighting men set out to go up against Ai. Joshua chose thirty thousand warriors and sent them out by night ⁴ with the command, “You shall lie in ambush against the city, behind it; do not go very far from the city, but all of you stay alert.