The celebration of Sukkos is a culmination of several cycles that occur every year. It is the last of the Shalosh Regalim, and Hashem now rests His Divine Presence on us completing the process of Yetzias Mitzrayim and kabbolas haTorah. Sukkos is also referred to in the Torah as the Chag Ha'asif - the Harvest Festival - thereby completing the agricultural year that had begun during the previous planting season. We also conclude the month of Tishrei, with its spiritual highs of Rosh Hashana and Yom Kippur, by celebrating Sukkos.
It appears that the agricultural aspect of Sukkos is merely physical in nature, and yet when analyzed more carefully there is a spiritual dimension even to the Harvest Festival. This celebration is closely linked to the post Rosh Hashana and Yom Kippur aspect of Sukkos. The Rambam (Hilchos Teshuva perek 9) elaborates on the relationship between blessing and success in this world and our ultimate reward for mitzvah observance. True reward for performance of mitzvos cannot take place in this world; the benefits of mitzvah observance are spiritual and thus are only appropriate in the spiritual setting of the next world. If so, why does the Torah elaborate upon physical things such as bountiful harvests as a reward for mitzvah performance? The Rambam explains that the promises are not as a reward but rather a mechanism to further mitzvah observance. We cannot serve Hashem properly without the physical blessings bestowed on us. These blessings are only significant as they enable us to continue in our performance of mitzvos.
Based on this Rambam, we can understand an otherwise strange tefillah recited by the Kohen Gadol on Yom Kippur. After experiencing the most intense spiritual encounter with Hashem, as he leaves the Kodesh Hakodoshim, the Kohen Gadol offers a fervent prayer. We would have expected this prayer to be spiritual in nature, and yet he prays for seemingly very materialistic blessings. Requests for bountiful crops and economic prosperity seem out of touch with the spiritual dimension of the day. However, if we understand the role of physical blessing as the enabler for future spiritual success, this prayer fits perfectly into the tone of the day.
The celebration of Sukkos as the Harvest Festival is not just about physical produce. By marking the bountiful harvest on the heels of the Yomin Noraim we are confirming our belief as to why Hashem grants us these seemingly materialistic blessings: our harvest is only meaningful if it furthers the spiritual goals attained during the weeks preceding Sukkos.
Today, most of us are not directly involved in the world of agriculture and it is difficult for us to relate to the notion of a Harvest Festival. Yet, the message of the role of physical bounty in the service of the spiritual is as true today as it was for our forefathers. As we celebrate Sukkos and express our thanks to Hashem for our bountiful physical "harvest," let us focus on its true worth as a way of enabling us to attain the spiritual "harvest" of Torah and mitzvos. With this mindset, the celebration of Sukkos is truly fitting as the culmination of the Rosh Hashana and Yom Kippur experience.