6 When you blow an alarm the second time, the camps that lie on the south side shall go forward. They shall blow an alarm for their journeys.
Numbers 10:6 Cross References - WEB
Numbers 2:10-16
10 “On the south side shall be the standard of the camp of Reuben according to their divisions. The prince of the children of Reuben shall be Elizur the son of Shedeur.
11 His division, and those who were counted of it, were forty-six thousand five hundred.
12 “Those who encamp next to him shall be the tribe of Simeon. The prince of the children of Simeon shall be Shelumiel the son of Zurishaddai.
13 His division, and those who were counted of them, were fifty-nine thousand three hundred.
14 “The tribe of Gad: the prince of the children of Gad shall be Eliasaph the son of Reuel.
15 His division, and those who were counted of them, were forty-five thousand six hundred fifty.
16 “All who were counted of the camp of Reuben were one hundred fifty-one thousand four hundred fifty, according to their armies. They shall set out second.
Numbers 10:18
18 The standard of the camp of Reuben went forward according to their armies. Elizur the son of Shedeur was over his army.