Reish Lakish said to Rabbi Yoḥanan: I should read here the verse: “You shall not cut yourselves [titgodedu]” (Deuteronomy 14:1), which is interpreted as meaning: Do not become numerous factions [agudot]. In other words, the Jewish people should be united, rather than divided into disparate groups that act in different ways. Before analyzing this issue, the Gemara asks: This verse: “You shall not cut yourselves,” is required for the matter itself, as the Merciful One is saying: Do not cut yourselves over the dead. How is the halakha concerning factions derived from this apparently straightforward verse?

Rav Kahana raised an objection against Rav and Rabbi Ḥanina from a baraita: There was an incident and the Sages decreed a fast on Hanukkah in Lod, and Rabbi Eliezer went down on that day and bathed in the bathhouse and Rabbi Yehoshua went down and cut his hair to show that they did not accept the fast. Furthermore, these two Sages said to the others: Go out and fast another fast as an act of penitence for what you have already fasted, as the days of Hanukkah are days of joy, on which fasting is forbidden. Hanukkah is one of the Festivals listed in Megillat Ta’anit. Even after the destruction of the Temple Hanukkah is celebrated, demonstrating that Megillat Ta’anit has not been nullified.

Rabbi Abba said that Rabbi Shimon ben Lakish said: Two Torah scholars who listen to each other in the discussion of halakha, the Holy One, Blessed be He, hears their voice, as it is stated: “You who dwell in gardens, the companions heed your voice, cause me to hear it” (Song of Songs 8:13). And if they do not do so, i.e., they do not listen to each other, they cause the Divine Presence to depart from among Israel, as it is stated in the following verse: “Run away, my beloved, and be like a gazelle or a young hart upon the mountains of spices” (Song of Songs 8:14).