Joshua 6:4-6

4Have seven priests carry trumpets of rams’ horns in front of the ark. On the seventh day, march around the city seven times, with the priests blowing the trumpets.

5When you hear them sound a long blast on the trumpets, have the whole army give a loud shout; then the wall of the city will collapse and the army will go up, everyone straight in.”

6So Joshua son of Nun called the priests and said to them, “Take up the ark of the covenant of the Lord and have seven priests carry trumpets in front of it.”