Josh 6:10

וְאֶת־הָעָם֩ צִוָּ֨ה יְהוֹשֻׁ֜עַ לֵאמֹ֗ר לֹ֤א תָרִ֨יעוּ֙ וְלֹֽא־תַשְׁמִ֣יעוּ אֶת־קוֹלְכֶ֔ם וְלֹא־יֵצֵ֥א מִפִּיכֶ֖ם דָּבָ֑ר עַ֠ד י֣וֹם אָמְרִ֧י אֲלֵיכֶ֛ם הָרִ֖יעוּ וַהֲרִיעֹתֶֽם׃

But Joshua had commanded the people: “Do not give a battle cry or let your voice be heard; do not let one word come out of your mouth until the day I tell you to shout. Then you are to shout!”