Of all the Jewish holidays, the one holiday that is singled out as a “Festival of Joy” is Sukkot. As the Torah in Deuteronomy 16:13-15 declares, חַג הַסֻּכֹּת תַּעֲשֶׂה לְךָ, שִׁבְעַת יָמִים…וְשָׂמַחְתָּ בְּחַגֶּךָ…וְהָיִיתָ, אַךְ שָׂמֵחַ , You shall make the festival of Sukkot for a festival day….You shall rejoice in your festival….and you will be completely joyous. That is why the rabbis call the festival of Sukkot, זְמַן שִׂמְחָתֵנוּ , the time of our rejoicing.
Sukkot: etrog, hadass (myrtle), lulav (palm), aravah (willow), the Sukkah, the festival sacrifice and the mitzvah to be happy.
There are many references of unity that are alluded to on the festival of Sukkot. The rabbis of the Talmud in Menachot 27a, state:
Of the four species that are used for the lulav, two are fruit bearing (the etrog and the lulav) and two are not (the myrtle and the willow). Those which bear fruit must be joined to those which bear no fruit, and those which bear no fruit must be joined to those which bear fruit. A person does not fulfill his obligation [of holding the lulav together with the other species] unless they are all bound in one band. And so it is with Israel’s conciliation with God, [it is achieved] only when they [the people] are all [bound together] in one band, as it is stated by the prophet Amos 9:6, He [God] Who builds His chambers in heaven, and founded His band upon the earth.
The Torah, in fact, explicitly relates the mitzvah of joy to the mitzvah of taking of the four species together. In Leviticus 23:40, it is written: You shall take for yourselves on the first day, the fruit of the citron tree, the branches of the date palms, twigs of a plaited tree, and brook willow; and you shall rejoice before the Lord your God for a seven day period.
The theme of unity is similarly found not only with the four species, but with the Sukkah itself. The Talmud in Sukkah 27b, states, that even though the rabbis declared that one may not use a borrowed lulav on the first day, nevertheless, one may sit in a sukkah belonging to a neighbor. As the verse in Leviticus 23:42 underscores: You shall dwell in booths for a seven day period, every native in Israel shall dwell in the booths. The Talmud concludes from the phrasing of the verse that all of Israel are worthy of sitting in one great big Sukkah.
An additional theme of unity and Sukkot is found in tractate Sukkah 2a. Citing the verse from Leviticus 23:43, בַּסֻּכֹּת תֵּשְׁבוּ שִׁבְעַת יָמִים , You shall dwell in the booths for seven days, the Talmud derives that, “Just as every Jew must leave his permanent dwelling place for seven days and live in a temporary dwelling place, so must every Jew on Sukkot live equally in a temporary dwelling, poor and rich alike.”
The festival of Sukkot marks the conclusion of the three pilgrimage festivals of the Jewish year where Jews all travel to Jerusalem and come together to celebrate in united happiness. It is only natural that on the last day of Sukkot, the festival of Simchat Torah, the rejoicing of the law, is celebrated. This is intended to teach that the true joy of Judaism is not only external, but internal. Consequently, the Al-Mighty is not satisfied with people only serving or worshiping God. The Torah expects the people to observe בְּשִׂמְחָה וּבְטוּב לֵבָב , with happiness and with a full heart.
The Torah, in Deuteronomy 28:47, warns that evil will befall the people, because they failed to serve the Lord amid gladness and goodness of heart when everything was abundant. Good Yom & Shabbat Shalom