Why did the three tribes that comprised Degel Machaneh Reuven (Reuven, Shimon and Gad), encamp specifically in the south?
Ramban (on Pasuk 2): Hashem said to Moshe: 'Reuven, the Ba'al Teshuvah, 1 shall encamp in the south, from where the dew and the rain of Berachah emanate - because Teshuvah is a good Midah, and Hashem's Mercy descends upon the world when the people do Teshuvah; and next to him is Gad, the mighty one, 2 with Shimon (the sinner) in the middle, so that they will atone for him. 3 They will travel second!' 4
See Rashi, Bereishis 37:29.
See Devarim 33:20.
To shield him from Ya'akov's curse (R. Chavel's footnotes).
Ramban: 'Because after Torah comes Teshuvah'.
