When ye blow an alarm,.... Making a broken, uneven, and quavering sound, which is called a "tara-tan-tara":
then the camps that lie on the east parts shall go forward; the camps of Judah, Issachar, and Zebulun, which lay to the east of the tabernacle, at the front of it; see Numbers 1:3; this was to be the token for their march, which was first of all; Numbers 10:14.