The war with מדין
In last week's parsha (מטות) we find that Moshe sends בני ישראל out to war against מדין. There are 2 very important points here:
1. The pasuk says that the army should be taken from all of the shevatim, לכל מטות ישראל, Rashi comments on this from the Sifri, לרבות שבט לוי, Shevet Levi also sent out soldiers to fight against מדין.
Everyone always quotes the Rambam that Shevet Levi did not go out to war, however, he we see Rashi based on the Sifri, argues with the Rambam and says explicitly that Shevet Levi did go out to war like all the other shevatim.
2. After the war, the soldiers come back with the women and children as captives. Moshe tells them kill all the adult women and all the male children. According to today's Western morality Moshe was committing war crimes and was doing something deeply immoral. And yet, Moshe did it and the Torah recorded it. It is clear that Moshe Rabbenu, who spoke face to face with Hashem and was בכל ביתי נאמן הוא, did not do anything immoral but did what the Torah required him to do. We see from here that Torah morality and Western morality don't go hand in hand and in fact many times are in conflict.