Musar su Giudici 18:30

Even though anger is a very bad quality, nevertheless, a man should conduct himself at times with the quality of anger. For example, when he rebukes the wicked, and when he desires to cause a spirit of awe and respect to dwell on the members of his household, and when he wants to obtain respect and even fear from his pupils. Even he who is angry with the wicked, must weigh the extent of his anger, for Moses, our teacher, upon whom is peace, said when he spoke wrathfully against Reuben and Gad : "A breed of sinful men" (Num. 32:14). And, therefore, we find that his descendant (the Levite mentioned in Judges 18:30) became a priest to idols, and this even though Moses was angry because he strove for the glory of God. Everything requires a proper measure in all a man's ways. A man should speak carefully how to do the commandments, whether he rebukes out of anger or rebukes joyously.

Chazal have said (Reishith Chochmah, Sha'ar Ha'anavah 4): "In three instances the Holy One Blessed be He overlooked idol worship; but He did not overlook machloketh. First, in the generation of Enosh, when men began to serve idols, as it is written: 'Then they began to call [idols] in the name of the L-rd.' But, because there was peace among them, the Holy One Blessed be He allowed them a hiatus. In the generation of the flood, however, because there was machloketh among them, so that they stole and plundered from each other, the Holy One Blessed be He did not relent, as it is written (Ibid. 6:"13): 'Because the earth was filled with violence by them, etc.' Second, in the generation of the desert when the Jews came to make the golden calf, the Holy One Blessed be He forgave them; but when they lapsed into machloketh, the Holy One Blessed be He did not overlook it. For wherever you find 'and they protested' [vayalinu] of machloketh, you find a great smiting, the most extreme instance being the Korach rebellion. Third, the image of Micah. Because there was peace among them, they were given a grace period, as it is written (Judges 18:30): 'And the children of Dan set up the image; and Yehonathan, the son of Menasheh, he and his sons were priests to the tribe of Dan until the day of the captivity of the land.' But when the tribes contended with the tribes of Judah and Benjamin, and there was no peace among them, they became scourges to each other. When the one sinned, the Holy One Blessed be He would bring the other upon him and exact payment from him, as it is written (II Chronicles 13:17): 'And Aviyya and his people slew them with a great slaughter, so there fell slain of Israel five hundred thousand chosen men.' And when the tribes of Judah and Benjamin sinned, the ten tribes came and exacted punishment of them, as it is written (Ibid. 28:6): 'For Pekach, the son of Remalyahu, slew in Judah a hundred and twenty thousand in one day.'" We are hereby taught that men of machloketh become instruments of destruction, one to the other.