Yehoshua 6:8-10

Orthodox Jewish Bible

⁸ And it came to pass, when Yehoshua had spoken unto HaAm, that the shivah Kohanim bearing the shivah shoferot hayovelim passed on before Hashem, and sounded the shoferot; and the Aron Brit Hashem followed after them.

⁹ And the armed men marched ahead of the Kohanim that blew with the shoferot, and the rear guard came after the Aron, with the shoferot of the Kohanim going on sounding.

¹⁰ Yehoshua had commanded HaAm, saying, Ye shall not shout, nor make any noise with your voice, neither shall any davar proceed out of your mouth, until the Yom I tell you to shout; then shall ye shout.