Numbers 10:7-9

International Standard Version

⁷ But when you blow the trumpet to assemble the whole congregation, don’t use the same sound as you do for sounding an alarm.^{[a] 8} The descendants of Aaron the priest are to blow the trumpets. Have them do this for you permanently throughout your generations to come.”

Sounding the Trumpet in Battle

⁹ “When you wage war in your land against an enemy who is hostile to you, you are to sound an alarm with the trumpets. Then you will be remembered before the face of the Lord your God and you will be delivered from your enemies.