Division and dispute also have power - destructive power. The damage they inflict is immeasurable, affecting both the spiritual and physical realms of existence, and their repercussions endure for generations. The story of the Mabul teaches that such disunions have brought humanity perilously close to extinction in the past.
Moreover, even actions taken with good intentions can lead to catastrophic outcomes when they result in discord. A fitting example of this can be found in the story of B'nei Yisroel as they stood on the verge of entering Eretz Yisrael, the Promised Land. The tribes of Reuven and Gad approached Moshe Rabbeinu requesting their own separate territories. Their rationale was their possession of large flocks of livestock. Rebbi Yehudah explains that they sought adequate grazing land that would prevent their animals from infringing upon the fields belonging to others.
However, this choice to separate themselves from the rest of their brethren carried long-term repercussions. Many years later, when the Aseres Hashevatim faced exile, it was the tribes of Reuven and Gad who were the first to be taken away. Rebbi Yehudah concludes: "וּמָה אִם שֶׁפֵּרְשׁוּ מֵחַבְרֵיהֶן כְּדֵי לְהִתְרַחֵק מִן הַגָּזֵל כָּךְ נֶעֶנְשׁוּ, הַפּוֹרְשִׁין מֵחַבְרֵיהֶן מִפְּנֵי הַשִּׂנְאָה וְהַקִּנְאָה וְהַתַּחֲרוּת עַל אַחַת כַּמָּה וְכַמָּה - If such dire consequences can result from well-meaning actions, how much more profound is the impact of divisions born of hatred, jealousy, and rivalry?"
(משנת רבי אליעזר פרשה ד)