Numbers 10:4

10:4 “But if they blow with one trumpet, then the leaders, the heads of the thousands of Israel, must come to you.

Numbers 10:6

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.

Numbers 10:8

10:8 The sons of Aaron, the priests, must blow the trumpets; and they will be to you for an eternal ordinance throughout your generations.