(42) You shall live in booths seven days; all citizens in Israel shall live in booths , (43) in order that future generations may know that I made the Israelite people live in booths [clouds of glory] when I brought them out of the land of Egypt, I the LORD your God.
(א) בסוכות תשבו שבעת ימים וגו' כי בסוכות הושבתי את בני ישראל הם ענני כבוד שהקיפם בהם לבל יכם שרב ושמש: ומצוה לתקן הסוכה מיד לאחר י"כ דמצוה הבאה לידו אל יחמיצנה [מהרי"ל]:
(1) On Succot we shall dwell for 7 days etc. Because on Succot I protected the children of Israel. These refer to the clouds of glory who protected them from all the intense heat and the sun of the desert. And it is a Mitzvah to begin building the Succah immediately after Yom Kippur. For if a Mitzvah that comes to one's hands, one should not delay performing it.
(א) כְּתִיב, בַּסֻּכֹּת תֵּשְׁבוּ שִׁבְעַת יָמִים, פֵּרוּשׁ, תָּדוּרוּ בַּסֻּכּוֹת. אָמְרָה תוֹרָה, שֶׁיָדּוּר בַּסֻּכָּה שִׁבְעַת יָמִים. כְּמוֹ שֶׁהוּא דָר בְּבֵיתוֹ כָּל הַשָּׁנָה, כֵּן תְּהֵא עַתָּה עִקַּר דִּירָתוֹ בַּסֻּכָּה, שֶׁיַכְנִיס לְתוֹכָהּ כֵּלָיו הַנָּאִים וּמַצָּעוֹת הַנָּאוֹת, וְאוֹכֵל וְשׁוֹתֶה וְלוֹמֵד וּמְטַיֵל וְיָשֵׁן בַּסֻּכָּה. וַאֲפִלּוּ אִם מְסַפֵּר עִם חֲבֵרוֹ, יְסַפֵּר בַּסֻּכָּה. וְכֵן אִם מִתְפַּלֵּל בִּיחִידוּת, יִתְפַּלֵּל בְּתוֹךְ הַסֻּכָּה. כְּתִיב, לְמַעַן יֵדְעוּ דֹרֹתֵיכֶם כִּי בַסֻּכּוֹת הוֹשַׁבְתִּי אֶת בְּנֵי יִשְׂרָאֵל בְּהוֹצִיאִי אוֹתָם מֵאֶרֶץ מִצְרָיִם, וְלָכֵן צְרִיכִין לְכַוֵּן בִּישִׁיבַת הַסֻּכָּה, שֶצִּוָּנוּ הַקָּדוֹשׁ בָּרוּךְ הוּא לֵישֵׁב בַּסֻכָּה זֵכֶר לִיצִיאַת מִצְרָיִם. וְסֻכּוֹת אֵלוּ שֶׁאָמַר הַכָּתוּב כִּי בַסֻּכּוֹת הוֹשַׁבְתִּי, נֶחְלְקוּ בָּהֶם תַּנָּאִים. רַבִּי אֱלִיעֶזֶר אוֹמֵר, הֵמָּה עַנְנֵי הַכָּבוֹד, שֶׁהִקִּיף בָּהֶם הַקָּדוֹשׁ בָּרוּךְ הוּא אֶת אֲבוֹתֵינוּ, לְבַל יַכֵּם שָׁרָב וָשָׁמֶשׁ. וְרַבִּי עֲקִיבָא אוֹמֵר, סֻכּוֹת מַמָּשׁ, שֶׁעָשׂוּ לָהֶם בִּשְׁעַת חֲנִיָתָן מִפְּנֵי הַחַמָּה. וְאַף עַל פִּי שֶׁיָצָאנוּ מִמִּצְרַיִם בְּחֹדֶשׁ נִיסָן, לֹא צִוָּנוּ לַעֲשׂוֹת הַסֻּכָּה בְּאוֹתוֹ הַזְּמָן, לְפִי שֶׁהוּא הַתְחָלַת יְמוֹת הַקַּיִץ, וְדֶרֶךְ כָּל אָדָם לַעֲשׂוֹת אָז סֻכָּה לְצֵל, וְלֹא הָיְתָה נִכֶּרֶת שֶׁהִיא בְּמִצְוַת הַבּוֹרֵא יִתְבָּרַךְ שְׁמוֹ. לָכֵן צִוָּה אוֹתָנוּ לַעֲשׂוֹתָהּ בַּחֹדֶשׁ הַשְּׁבִיעִי, שֶׁהוּא זְמַן הַגְשָׁמִים, וְדֶרֶךְ כָּל אָדָם לָצֵאת מִסֻּכָּתוֹ וְלֵישֵׁב בְּבֵיתוֹ. וַאֲנַחְנוּ יוֹצְאִין מִן הַבַּיִת לֵישֵׁב בַּסֻּכָּה, בָּזֶה יֵרָאֶה לַכֹּל, כִּי מִצְוַת הַמֶּלֶךְ הִיא עָלֵינוּ לַעֲשׂוֹתָהּ.
(1) It is written "For seven days teishvu in sukkos," (Leviticus 23:42), which means "you must dwell" in sukkos. The Torah teaches that you should make the sukkah your home for seven days. Just as you live in your home all year, so now [on Sukkos] the sukkah should be your principal residence. There you should bring your fine china and elegant tablecloths. You should eat, drink, study,1You must study Torah in the sukkah only if you are able to concentrate with total peace of mind. However, when because of cold weather you are unable to remain there for an extended period, to study with concentration, you are exempt, and may study in your home or in the Beis Midrash. (Mishnah Berurah 639:29) spend your leisure, and sleep in the sukkah. Even conversation with friends2However, because of the sacred nature of the sukkah, you must be very careful not to speak about forbidden subjects, gossip or slander. (Ibid 639:2) should be held in the sukkah, and if you pray alone3If however there is a synagogue in your area, you must leave the sukkah and attend the synagogue because during the rest of the year, you also leave your house to pray in the synagogue. (Ibid 639:30) you should also pray in the sukkah. It is written, "This is so that future generations will know that I caused the Israelites to live in sukkos when I brought them out of Egypt," (Leviticus 23:43). Therefore, you should keep in mind when you live in the sukkah, that the Holy One, blessed is He, commanded us to live in the sukkah as a memorial of the Exodus from Egypt. Regarding the sukkos of which the verse says "That I caused [the Israelites] to live in sukkos, there is disagreement among Taanaim. Rabbi Eliezer says that it refers to the Clouds of Glory with which the Holy One, blessed is He, surrounded our forefathers, to shield them from the heat and the sun. Rabbi Akiva, says that it means actual sukkos that they built for themselves when they camped [in the desert] as a protection from the sun. Although we departed from Egypt in the month of Nisan, He did not command us to build the sukkah during that season, because it is the beginning of the summer, when people usually build booths for the shade, and it would not be recognized as being built in order to fulfill the mitzvah of the Creator, blessed is His Name. He, therefore, commanded us to make it in the seventh month, which is the rainy season, when people usually move out of their booths to live in their homes; but we move out of our houses to live in the sukkah; which makes it clear to all that we are fulfilling the King's command.
RAC, "Sukkot Environment: An Overview"
The seven days we spend in the sukkah allow us to interact with the environment around us in a way that our permanent homes do not. Eating and sleeping in sukkot force us to feel the wind, breathe the outside air, and gaze at the sun, moon, and stars.
Baal Shem Tov
"We build a sukkah to remember the hardships our ancestors suffered while tending the land. 'Forgetfulness leads to exile while remembrance is the secret of redemption,” wrote the Baal Shem Tov.