Seudat Siyum Masechet
Based on the Talmud and Midrash, the seudah celebration upon the completion of a Talmudic tractate is considered a seudat mitzvah (Yam Shel Shlomo, Bava Kamma, Merubah 37; Maharam Mintz 119; Shach, Yoreh De'ah 246:37). This seudah is made to rejoice over the accomplishment, and also to motivate and inspire others to do the same. Rabbi Chaim Elazar Shapiro (the "Munkatcher Rebbe") observes in his work Sha'ar Yissachar that the evil inclination does not want to see this type of shared joy, noting that one of the names of the evil inclination, "Sama'el," may be seen as an acronym for Siyum Masechet Ain La'asot, or "do not make a siyum".
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