Numbers 10:3-8

³And they shall blow with them, and bring all the congregation together unto thee, at the door of the tabernacle of ordinance.

⁴And if they blow with but one, the chiefs, the heads of thousands of Israel, shall gather together to thee.

⁵When you blow with a full note, (or alarm,) the host that encampeth eastward shall go forward,

⁶and when you blow with the second alarm, the hosts that encamp southward shall go on; an alarm shall they blow for their journeys.

⁷But when the congregation is to be gathered together, you shall blow, but not with the alarm.

⁸And the sons of Aharon, the priests, are to blow with the trumpets; and this shall be to you a perpetual statute for your generations.