To whom does "ha'Ezrach" refer?
Rashi (according to the Ramban): "Ezrach" refers to the men; "ha'Ezrach" precludes women. 1 If not, we would have included them due to a Gezeirah-Shavah "Chamishah Asar-Chamishah Asar" from Matzah.
Moshav Zekenim (24): Even though they are exempt, since they are accustomed to fulfill, they may bless. The same applies to Shofar, Kri'as ha'Torah, Aliyah l'Regel; some virtuous women bless on Talis and Tefilin..
What are the implications of "Succos"?
Targum Onkelos and Targum Yonasan: 'Succos has connotations of shade (the basic purpose of a hut). 1
Targum Yonasan:Consequently, it must be contain more shade than sun and must be specifically built for the sake of the shade
Why does the Torah add the word "Kol"?
Rashbam: To obligate even people who own houses (Bechor Shor - great mansions) to live in a Sukah on Sukos.
Ramban, Moshav Zekenim: Perhaps we expound 'Kol Asher k'Ezrach', i.e. those who are Ra'anan (robust) in their houses, to exclude people at sea and travelers.
Why does it add the word "b'Yisrael"?
Rashi: To include converts in the law of Sukah.
Torah Temimah (citing Sukah, 27b): The Gemara learns from this Pasuk 1 that all Yisrael are able to sit in one Sukah - in other words, although a borrowed Lulav is Pasul, a borrowed Sukah is Kasher.
Torah Temimah: Since the Pasuk begins in the singular ("Kol ha'Ezrach
Why does it say "ba'Sukos" three times (including once in the coming verse)?
Moshav Zekenim (from Sanhedrin 4a): This is a hint that a Sukah must have three walls; one of them may be a mere Tefach. 1 R. Shimon holds that Yesh Em l'Mikra, so he requires four walls, and one of them may be a mere Tefach.
Targum Yonasan: The other two must measure at least seven Tefachim, whereas the minimu height of the Succah is ten Tefachim.
What do we learn from "Teshvu"?
Moshav Zekenim (from Sukah 28b): One dwells in the Sukah like in his house, i.e. day and night, and with his wife, even though women are exempt from Sukah.
How do we infer (Sukah 28b) from "Teshvu" that one dwells in the Sukah like in his house?
Moshav Zekenim: It relies on the coming verse. "Doroseichem" is written Chaser (without a Vov), so it can be read Diraschem.
Why does it say both "Teshvu" and "Yeshvu"?
Moshav Zekenim #1: If one did not have a Sukah on the first day, he makes one during Chol ha'Mo'ed. All 1 agree that if it fell, he rebuilds it.
Moshav Zekenim #2: People who travel during the day must dwell in a Sukah at night, and people who travel during the night must dwell in a Sukah during the day.
I.e. even R. Eliezer, who holds that a Sukah must be for seven days, and if one did not have a Sukah on the first day, he does not build one during Chol ha'Mo'ed. (PF)
Why did the Torah command to sit in Sukos at the beginning of the rainy season, and not in the summer? It would be more appropriate in Nisan, for it commemorates Yetzi'as Mitzrayim!
Moshav Zekenim: If it were in summer, it would seem like we go to Sukos due to the sun. Rather, we go at the beginning of winter, when others go from huts to their houses due to rain. It is clear that we do oppositely due to Hashem's Mitzvah.
Ramban (43), Moshav Zekenim (43): According to the opinion that Sukos commemorates the huts that Bnei Yisrael made in the Midbar, they made them at the beginning of winter, when it begins to get cold.
Kol Eliyahu, Divrei Eliyahu: Sukos commemorates the Clouds of Glory. They departed after Chet ha'Egel, and returned when they began to make the Mishkan. Moshe descended [from Har Sinai] on Yom Kipur, and commanded about the Mishkan the next day. People brought donations "ba'Boker ba'Boker" (the next two days), On the 14th of Tishrei, Chachamim took the required amount of gold from Moshe, and on the 15th they began building the Mishkan 1 , and the Clouds returned.
We fast and say extra Tachanunim on Monday and Thursday, for they are Yemei Ratzon (Rema OC 134:1). The Vilna Gaon himself cites Tosfos (Bava Kama 82a DH Kedei, based on Tanchuma (Bereishis 19:24) and Bereishis Rabah 76), that it is because Moshe ascended to receive the second Luchos on Thursday, and he descended on Yom Kipur on Monday. If so, the 15th was Shabbos! Perhaps they began Meleches ha'Mishkan in ways for which one is exempt on Shabbos and Chachamim did not yet forbid, e.g. (Shemos 35:26) they spun attached goat hair (Shabbos 74b), or two did a Melachah together, and each could have done it himself (Shabbos 10:5). (PF)
What is the primary Mitzvah of dwelling in the Sukah?
Moshav Zekenim: It is sleeping. We find that one may eat Arai (not in a fixed manner) outside a Sukah, but one may not sleep Arai outside a Sukah (Sukah 26a). 1
Moshav Zekenim: We do not bless on sleeping in a Sukah, lest he be unable to sleep, and his Brachah was l'Vatalah.
QUESTIONS ON RASHI
Rashi writes that "b'Yisrael" includes converts. We should know this already from "Torah Achas
Ramban, Moshav Zekenim: This obligates everyone, big and small. Do not say that it suffices for one member of the household to dwell in a Sukah, and the rest dwell in the house.