Yevamos 13b-14b
What are the parameters of the prohibition of dividing into factions? \u2022 Is Lo Sisgodedu a biblical or rabbinic prohibition? \u2022 Is it permitted for residents of walled cities to read the Megillah on the 14th of Adar? \u2022 Is making an unnecessary blessing a biblical or rabbinic prohibition? \u2022 What is a Bas Kol, heavenly voice, and its role in Halacha? \u2022 Is one who considers something permitted nonetheless required to help another avoid doing something that would be prohibited based upon that person's stringency?