Joshua 6:4-5

Also seven priests shall carry seven trumpets of rams’ horns before the ark; then on the seventh day you shall march around the city seven times, and the priests shall blow the trumpets. It shall be that when they make a long blast with the ram’s horn, and when you hear the sound of the trumpet, all the people shall shout with a great shout; and the wall of the city will fall down flat, and the people will go up every man straight ahead.”