Numbers 10:5-7
10:5 When you blow an alarm, then the camps that are located on the east side must begin to travel.
10:6 And when you blow an alarm the second time, then the camps that are located on the south side must begin to travel. An alarm must be sounded for their journeys.
10:7 But when you assemble the community, you must blow, but you must not sound an alarm.
Numbers 10:9
10:9 If you go to war in your land against an adversary who opposes you, then you must sound an alarm with the trumpets, and you will be remembered before the Lord your God, and you will be saved from your enemies.