Numbers 10:1-5

1 The Silver Trumpets
The Lord said to Moses:

2 “Make two trumpets of hammered silver, and use them for calling the community together and for having the camps set out.

3 When both are sounded, the whole community is to assemble before you at the entrance to the Tent of Meeting.

4 If only one is sounded, the leaders—the heads of the clans of Israel—are to assemble before you.

5 When a trumpet blast is sounded, the tribes camping on the east are to set out.