Daf Yomi - Sukkah 12 - Highlights

1. Rabbi Yochanan cites a source regarding the two halachos of s’chach. The verse states that the s’chach should come from the refuse of the threshing floor and from the wine vat. The refuse is not susceptible to tumah and does not grow from the ground. (12a1)
2. The Mishna states that one cannot use bundles of straw or twigs as s’chach, but if he unties them, they are valid as s’chach. All these bundles are valid for the walls of the Sukkah. (12a2)
3. Rabbi Yochanan maintains that the reason that one cannot use bundles of straw as s’chach is because we are concerned that he will place bundles on top of his sukkah to dry them. Although he does not intend that the bundles be used as shade, he will later change his mind to use the bundles for s’chach. Doing so would invalidate the s’chach because it would be a problem of taaseh v’lo min hasauy, you shall make, and not use that which was already made. For this reason it is always prohibited to use bundles for s’chach, even when he places the bundles for the purpose of providing shade. (12a2-12a3)
4. If one burrows a sukkah out of a haystack, it is invalid because it would be a problem of taaseh v’lo min hasauy, you shall make, and not use that which was already made. (12a2-12a3)
5. A Sukkah that is invalid because of taaseh v’lo min hasauy is biblically invalid. Nonetheless, if it cannot be used as a Sukkah on account of a rabbinical decree of taaseh v’lo min hasauy, then it will only be rabbinically forbidden. (12a4-12b1)
6. Male arrow-shafts, i.e. the solid tip of a shaft is placed into a cavity in the arrowhead are valid for s’chach because they do not have a receptacle and thus they are not susceptible to tumah, however female ones are invalid for they contain a receptacle and therefore are susceptible to tumah. This is a novel Halacha for we might have thought that since it is permanently filled, it is not deemed a receptacle and therefore not susceptible to tumah.
7. S'chach made of (processed) combed flax is invalid, however if it is made from flax before the flax was soaked, it is valid. Rabbi Yochanan is uncertain as to what the Halacha is in this case. There is a question regarding what phase of the flax process we are referring to.