Numbers 10:1-9 King James Version (KJV)
10 And the Lord spake unto Moses, saying,
2 Make thee two trumpets of silver; of a whole piece shalt thou make them: that thou mayest use them for the calling of the assembly, and for the journeying of the camps.
3 And when they shall blow with them, all the assembly shall assemble themselves to thee at the door of the tabernacle of the congregation.
4 And if they blow but with one trumpet, then the princes, which are heads of the thousands of Israel, shall gather themselves unto thee.
5 When ye blow an alarm, then the camps that lie on the east parts shall go forward.
6 When ye blow an alarm the second time, then the camps that lie on the south side shall take their journey: they shall blow an alarm for their journeys.
7 But when the congregation is to be gathered together, ye shall blow, but ye shall not sound an alarm.
8 And the sons of Aaron, the priests, shall blow with the trumpets; and they shall be to you for an ordinance for ever throughout your generations.
9 And if ye go to war in your land against the enemy that oppresseth you, then ye shall blow an alarm with the trumpets; and ye shall be remembered before the Lord your God, and ye shall be saved from your enemies.