The last day of Succot is a combined שמיני עצרת and שמחת תורה bunched into one day. It is considered a חג בפני עצמו, a holiday in itself, which is why we say שהחיינו while lighting candles or making Kiddush.
It is a reflection of G-d’s love for Israel. Hashem says, קשה עלי פרידתכם, “It is difficult for Me to part from you.” He wanted that special bond of the Chagim to extend for one more day. The next reunion would only come after the long, cold winter, on Pesach.
On this day, we say תפילת גשם, the prayer for rain, Yizkor, to remember our beloved family members, and Hakafot, when we celebrate the completion of the Torah.
We are meant to reflect and appreciate the gift given to the Jewish people, and the world. There is no book that compares to the Torah, for it is the only book written by G-d, Himself, as dictated and taught to Moshe Rabbeinu.
The depth of the understanding of the Torah, is limitless. Because of its Divine writing, it can be understood in four ways. This is known as פרדס, or orchard. Each letter of the word, פרדס, reflects a different level of comprehension. The letter “פ” refers to פשט, or a simple understanding of the text. The “ר” is רמז, or hints, that allows a Torah student to delve deeper into what is “hinted,” in the text. The “ד” is דרש, which goes even deeper into exploring what is derived from the Torah’s instructions. And the “ס” refers to סוד, or the secrets hidden in the Torah. This can include Kabbalistic teachings where much is learned from גמטריא, or, numerical equivalents, or other secrets of the Torah.
The study of Torah is probably the most worthwhile endeavor, for a Jew. The rewards are without end, and give each individual a reason for living. It is clear why we celebrate שמחת תורה, but it is also clear that every individual needs to have the resolve to study more Torah in the coming year. Chag Sameach!