The Command To Rejoice
Of all the holidays throughout the year, our joy is greatest on Sukkot, the "festival of our rejoicing."
The commandment to rejoice on Sukkot appears three times in the Torah. By contrast, there is no specific command to rejoice on Passover, and the command to rejoice on Shavuot appears only once.
Why is our joy greater on Sukkot? And why are we commanded to be happy three separate times?
The Midrash explains that the joy of a festival is directly related to the particular stage of the harvest when it occurs.
On Passover, which occurs in the spring, the grain in the fields has just begun to grow. Because one is not yet sure of the eventual yield, our joy is limited. Accordingly, there is no commandment to rejoice in the Torah. By Shavuot, the grain has ripened and is ready to be harvested. Our joy is not complete, however, for although it is gathered together, it must remain in the field and cannot yet be eaten. Thus, the commandment to rejoice appears only once.
On Sukkot, the grain is brought from the fields into our homes. Because the grain can now be utilized and fully enjoyed, our joy is greatest. The commandment to rejoice on Sukkot appears three times.
A deeper contemplation of this concept reveals that the events we celebrate on each holiday are also related to the particular time of year in which it falls.
On Passover, the Jews left Egypt. Yet they were still at the beginning, like grain that has just begun to germinate. On Shavuot, the Jews received the Torah, but they had not yet begun to observe it. This is like a harvest which has ripened but has not yet been brought indoors. On Sukkot, the Jewish people observed the Torah's commandments of their own volition. The "harvest," as it were, was finally being utilized.
These three periods are also reflected in the spiritual service of every Jew:
The first stage, "spring," is symbolic of a Jew's pure faith in G-d, the foundation of Torah and mitzvot. But faith does not necessarily lead to practical observance, just like on Passover one is still unsure whether the wheat will flourish. This is the "spiritual Passover" of the Jew.
Reaping the grain is next, but it is not the culmination of the process. In the spiritual sense, this is equal to a Jew's resolve to keep the Torah before he has begun acting. The "harvest" is still in the field; hence a Jew's "spiritual Shavuot."
It is only when the grain is eaten, when the Jew's resolutions for good find expression in actual deed, that perfection is achieved. This is the "spiritual Sukkot" of the Jew. Thus the highest level of joy is felt on Sukkot, and it is truly " the time of our rejoicing."
Adapted from Likutei Sichot of the Rebbe, Vol. 29