Cross reference
Joshua 6:8
8 It was so, that when Joshua had spoken to the people, the seven priests bearing the seven trumpets of rams' horns before Yahweh passed on, and blew the trumpets: and the ark of the covenant of Yahweh followed them.
Numbers 32:20
20 Moses said to them, If you will do this thing, if you will arm yourselves to go before Yahweh to the war,
Joshua 6:3-4
3 You shall compass the city, all the men of war, going about the city once. Thus shall you do six days.
4 Seven priests shall bear seven trumpets of rams' horns before the ark: and the seventh day you shall compass the city seven times, and the priests shall blow the trumpets.