As we continue our journey through this tractate, the rabbis find more ways to explore what it means that the sukkah is a temporary structure. This dafbegins a sugya (a general legal theme or topic) that deals ostensibly with whether one can reuse a kosher sukkahfrom a previous year or a structure originally built for a different purpose, such as protection from the sun for workers in the fields or for watchmen keeping guard over crops before they are harvested. The Gemara raises two broader principles in this discussion: intention and agency.
The mishnah on today’s page reads:
Beit Shammai says that an old roof is pasul (unacceptable). Beit Hillel says it is acceptable. What is an old sukkah? Anything that was built thirty days before the festival begins.
Beit Shammai and Beit Hillel are arguing specifically about the roof of the sukkah because, as has become clear over the course of this tractate so far, the roof, which is made of s’chach (branches), is the defining feature of the sukkah. The sukkah is nothing without its s’chach.
Beit Shammai says any reused roof is unacceptable, though Beit Hillel permits reuse of roofing material. The medieval commentator Rashi explains that Shammai is specifically talking about a situation in which the sukkah was not built for the festival. How do we know? Beit Shammai holds that to fulfill the mitzvah one has to have intention,specifically for the sake of the mitzvah. There is a tradition that one starts studying the laws of festivals thirty days beforehand (Pesachim 6a). It is assumed, therefore, that if it is built within this window of study, it was built for Sukkot.
However, according to Hillel, if the sukkah is built specifically for the festival and for no other reason, then even if it was built much earlier — at the start of the previous year — it is permitted.
Hillel and Shammai famously disagree throughout the Talmud. But though they disagree on this page as well, they do fundamentally seem to agree that intent is important. It is a longstanding argument throughout the Talmud as to whether one must have intent or not to fulfill a mitzvah. One position is that intention is essential, otherwise the exercise is meaningless and routine. But not all rabbis agree on this — at least not all the time. The other point of view is that it is the act that counts because the intention is very difficult to control or verify. As one saying repeated five times in the Talmud has it: From doing a mitzvah for the wrong reason one may come to do it for the right reason.
Read all of Sukkah 9 on Sefaria.