There is a positive Biblical command to reside in a Sukkah for seven days. These days are from the fifteenth of the month of Tishrei until and including the twenty first. The source for this is the Torah portion of Emor (Vayikrah 23.34): "On the fifteenth day of the seventh month will be the festival of Sukkos, a period of seven days dedicated to G-d...in a Sukkah you should dwell for seven days, in order that your generations know that in Sukkos did I cause the Children of Israel to dwell when I took them out of the land of Egypt" (23.42 - 23.44).
The Braisa in Gemara Sukkah (12.2) teaches as follows:
- " '... that in Sukkos did I cause the Children of Israel to dwell ...' - These are the clouds of glory. These are the words of Rabbi Eliezer. Rabbi Akiva says that these Sukkos were actual physical dwellings that they made for themselves."
Now, in regard to Rabbi Eliezer it certainly makes sense to have a commemoration for such a momentous supernatural event, to be esconced in these 'clouds of glory'. The miraculousness of these clouds is also mentioned in Nechmia (9), at the time of the ingathering from the Assyrian Exile, where it states: "Even though they made for themselves the golden calf...you in your great mercies did not abandon them in the desert, the clouds of glory you did not remove from them...or the pillar of fire at night...". These clouds of glory were visible manifestations of G-d's presence, as Moshe our teacher clearly stated during the incident of the spies: "...that eye to eye they have seen you G-d, and your clouds stood above them, and you led them with a pillar of cloud by day, and a pillar of fire at night." (Bamidbar 14.14).
On the other hand, according to Rabbi Akiva, what is so momentous about the fact that they lived in these huts, that the Torah should say "that your generations will know that in Sukkos I caused...etc"?
(Rabbi Akiva is of the opinion that a Sukkah is not a sensible metaphor for the clouds of glory. One cannot make a replica of the clouds, and one does not derive a law from a source that is not part of the natural order or is otherwise impossible conceptually. Rabbi Eliezer does not see this as an impediment to derivations. This argument follows their respective positions on the issue, as is seen in Gemara Menachos (82.1) in the discussion of impossibility of using tithed animals for the Peasach sacrifice at the time of the Exodus, see there.)
This questions is answered thusly: The momentous event commemorated by the Sukkos was the outstanding behavior of the Jewish People in the desert, that they willingly traveled - men, women, and children, tens of thousands - in a place where it is not in the nature of people to dwell. The verse testifies to this itself: "an area bereft of vegetation". Similarly the prophet exhorted the Jewish people (Yirmiyah 2.31) : "Was I a desert to Israel, or a land of deep darkness?", meaning to say: 'In the desert I prepared for them all their needs, nothing was lacking.’ Similarly, Moshe our teacher states in the portion of Devarim: "You know as you traveled the desert these forty years that the L-ord your G-d was with you, and you lacked nothing."
The result of all this is that the core of this commandment is to create a remembrance of the ordeal in the great wilderness, that aside from the lack of vegetation, they did not even have homes, only temporary huts. Therefore, we were commanded to build Sukkahs as a demonstration, in order to commemorate the lofty level we had reached under the direct providence of G-d that was experienced upon leaving Egypt.
This is the language of the Tur:
- "The Torah has made the Mitzvah of Sukkah dependant on the Exodus, along with many other commandments, since our eyes have seen it and our ears have heard it, and no man can deny its occurrence. It is a testimony to the existence of the Creator, who created all according to His will and who has the power, control, and ability to direct all that happens on high and in the lower world, to do with them as He wills, as he had done with us when he brought us forth form Egypt with signs and wonders. Sukkos specifically relates to the clouds of glory, with which they were surrounded, protecting them from the elements. He therefore commanded us to make Sukkos in order to remember his wonders and awesome acts."
- "Even though the Exodus was in the month of Nissan, we were not commanded to make a Sukkah at that time in the days of the summer, since at that time many people make themselves a type of hut as a source of shade, and building the Sukkah for the sake of G-d's command will not be recognizable. Therefore we are commanded to construct it in the seventh month, during the rainy season, which is a time when people leave their outdoor dwellings for the protection of their house. At this time we leave the house to dwell in a Sukkah, and thereby demonstrate to all that this is the result of G-d's command to build a Sukkah."
Until here is the quote. This is a satisfactory reason within the realm of 'Pshat' (the reasonable and apparent explanation).
There is also another good reason for the placement of this Mitzvah in the month of Tishrei and not Nissan, and that is that G-d wanted to demonstrate that even though we have sinned he had not removed his providence from upon us, and we still 'resided in his shade' and had 'refuge under his wings'. Just as after the giving of the Torah the golden calf was constructed, and in spite of that the Holy One Blessed be He was willing to bestow the second tablets on the day of Yom Kippur, follow that with His command to contsruct the Tabernacle after Yom Kippur, so that his presence should have a place to 'dwell', as it is written: 'I will dwell among the Children of Israel', and maintain the presence of the clouds of glory, as we mentioned was written in Nechemia.
Through this Mitzvah that G-d commanded us the same idea is taught to future generations, that though we may have sinned all year long, on Yom Kippur our sins are forgiven, as long as we return to Him with repentance. The fact that we are commanded immediately following Yom Kippur to build a Sukkah is the sign that we have returned to be under the shade of the presence of the Holy One, Blessed be He, as it is written (Shir Ha'Shirim 2.3): 'in His shade I delighted and sat,' - that is the Mitzvah of Sukkah, 'and His fruit was sweet to my palate' - that is the Mitzvah of the Esrog, as our Rabbis of blessed memory state in the Midrash Chazis. Their lesson is that after all the indiscretions He still has a love for us, and supervises our fate to save us from troubles and damage, and endeavors to return us to be under His holy and pure shade, and the Blessed One is as a covering upon us. (This is why the Hebrew word Sukkah equals G-d's name in gematria).
When one sits in the Sukkah he should be aware that the Holy One blessed be He commanded us to sit in the Sukkah as a remembrance of the exodus (Magen Avraham and Bach). This means to say: That though there is a position that Mitzvah performance requires awareness, that is usually limited to the awareness that one is fulfilling that Mitzvah. The Sukkah, however, requires an additional awareness, since the Torah demanded that 'future generations know that in Sukkahs I caused the Children of Israel to dwell when the left Egypt', which means that during the MItzvah's performance one should know and intend that the reason for the commandment is to remember the exodus from Egypt (Machatzis HaShekel).
We have already noted in the previous section that there is a MItzvah to build the Sukkah immediately after Yom Kippur, for 'a Mitzvah that comes to one's hand should not be delayed’, and 'the Zealous are quick to pursue Mitzvah performance'.