Cross reference
Numbers 10:7
7 But when the assembly is to be gathered together, ye shall blow, but ye shall not sound an alarm.
Joel 2:1
1 Blow ye the trumpet in Zion, and sound an alarm in my holy mountain; let all the inhabitants of the land tremble: for the day of Jehovah cometh, for it is nigh at hand;
Numbers 10:3-4
3 And when they shall blow them, all the congregation shall gather themselves unto thee at the door of the tent of meeting.
4 And if they blow but one, then the princes, the heads of the thousands of Israel, shall gather themselves unto thee.