Daf Yomi - Sukkah 9 - Highlights

There is a debate regarding a Sukkah that was made more than thirty days prior to Sukkos and was constructed with a specific intention to be used for Sukkos. Bais Shammai maintains that the Sukkah is invalid because it was not made for the sake of the mitzvah whereas Bais Hillel maintains that the Sukkah is valid. (9a1)
There is a debate regarding what is derived from the verse that states the festival of Sukkos, for seven days, unto HaShem. Bais Shammai maintains that we derive from this verse that a Sukkah must be constructed for the sake of the mitzvah and Bais Hillel maintains that just like the Heavenly Name attaches itself upon a Chagigah offering, so too the Heavenly Name attaches itself upon a Sukkah. Bais Hillel derives this from the fact that it is said the festival of Sukkos, for seven days, unto HaShem. The juxtaposition of the word chag, which alludes to the Chagigah sacrifice, to the word haSukkos, which means the Sukkah, teaches us that just like the Chagigah is sanctified to HaShem and one cannot benefit from the Chagigah, so too the Sukkah is sanctified to HaShem and one cannot derive benefit from the Sukkah. (9a1)
Bais Hillel maintains that one can build a Sukkah on Chol HaMoed and Bais Shammai maintains that one cannot build a Sukkah on Chol HaMoed. (9a1-9a2)
Bais Hillel maintains that a Sukkah does not have to be made for the sake of the mitzvah because the Torah does not state such a requirement. Regarding the making of tzitzis, however, it is said you shall make for yourself twisted cords, and this teaches us that the tzitzis must be made for the sake of the mitzvah. The verse regarding making a Sukkah that states the festival of Sukkos you should make for yourself teaches us that one cannot fulfill his obligation of making a Sukkah with stolen materials. (9a2)
The Mishnah states that a Sukkah built under a tree is invalid. If one builds one Sukkah on top of another Sukkah, the Chachamim maintains that the upper Sukkah is valid and the lower Sukkah is invalid, whereas Rabbi Yehudah maintains that if there are no tenants in the upper Sukkah, the lower one is valid. (9b1)
Rava states that the ruling of the Mishnah that building a Sukkah under a tree is invalid is only when the shade of the tree is greater than its sunlight. When the sunlight of the tree is greater than its shade, the Sukkah will be valid when he lowers the tree branches and intermingles them with the valid s’chach. The invalid s’chach is thus nullified and we deem the Sukkah to be entirely covered with valid s’chach. (9b1)
Rabbi Yirmiyah maintains there is a situation regarding a Sukkah on top of another Sukkah when both are valid. There is a situation where both Sukkas are invalid. There is a situation where the lower Sukkah is valid and the upper Sukkah is invalid. There is also a situation where the lower Sukkah is invalid and the upper Sukkah is valid. (9b2)