Every Jewish holiday commemorates something. Chanukah celebrates the Maccabean victory over the Syrian Greeks. Purim celebrates Mordechai and Esther’s victory over Haman in ancient Persia. Passover celebrates the Exodus from Egypt. Other holidays celebrate major events in Jewish history. Shavuot celebrates receiving the Torah at Mount Sinai. Sukkot celebrates the miraculous cloud canopy that protected our ancestors during their forty-year journey across the desert.

Shemini Atzeret is the only holiday that doesn’t seem to celebrate anything. The Torah tells us Atzeret,  refrain from work on this day. But why? What happened on this day that warrants a holiday?

On the one hand, it is appended to Sukkot, a seven-day holiday. This is implied by its name: the eighth day. On the other hand, the Talmud (Sukkah 48a) explains that it is an independent holiday and not part of Sukkot. Firstly, it has a different name, Shemini Atzeret, not Sukkot. Secondly, the order of the offerings brought in the Temple on this day was radically different from the offerings brought during Sukkot. Also, one recites the Shehechiyanu blessing on this festival because it is the first time it has been celebrated since the previous year. Clearly, it is not merely an extension of Sukkot.

If it is its own holiday, what is its significance? What does it celebrate or commemorate?

On One Foot
The Talmud (Shabbat 31a) relates a story about a proselyte who asked the great sage Shammai to teach him the entire Torah on one foot. Shammai assumed he was mocking him and had him removed from the building. The man went to Hillel and repeated the question, and Hillel said, “What you don’t want done unto you, do not do unto others. This is the entire Torah; the rest is commentary. Go and study it.”

Much ink has been spilled on this story. Some suggest that the proselyte misspoke. He meant to ask for the one principle upon which the entire Torah stands. Instead, he asked for the entire Torah while standing on one foot. Hillel understood the intent; Shammai heard the spoken words (Kli Yakar Leviticus 19:18).

I want to share a daring interpretation. The proselyte was not talking about a foot at all. He was talking about the Jewish festival, Shemini Atzeret, that we have been discussing.

Judaism has long referred to the three pilgrimage festivals, when Jews made pilgrimage to the ancient Temple in Jerusalem, as the three regalim. The word regel means foot. The proselyte asked the very question we have been posing. I understand all three pilgrimage festivals, the regalim, the foot festivals. But I fail to understand the regel achat, the one leg, the one-day pilgrimage appended to the end of Sukkot. Can you make sense of it for me? What does it signify? What does it commemorate?

The Golden Rule
This is where Hillel’s deep insight comes into play. Shammai thought he was asking for the Torah to be taught to him on one foot. Hillel understood that he was asking to be taught the Torah of the one regel, the one festival that seems to commemorate nothing. So Hillel replied with the golden rule: What you don’t want done unto you, don’t do unto others. This is the entire Torah of the regel achat, the one-day festival.

Rashi (Leviticus 23:36) quotes the Talmud when addressing this festival. G-d says to the Jewish people, “Your parting is difficult for me. I beg you to stay one more day.” The simple meaning is that I am loath to part with my children. You have spent the entire Sukkot with me, and I can’t stand seeing you part company with me. Please stay another day.

Notice, however, that G-d only says, “Your parting” is difficult for me. He doesn’t specify whom they are parting from. Since it is G-d talking, we assume He is referring to our parting from Him. But there is a much deeper understanding of these words: “Your parting from each other is difficult for me.”

For seven days, you were away from your private homes, fortunes, and challenges. You left your personal concerns at home and spent time focused on each other. As a father, G-d takes great joy in seeing His children united. But now, with Sukkot drawing to a close, G-d looks ahead and sees our departure. We will each return to our own concerns and achievements, and think much less about each other. While this is the normal human pattern, it is difficult for G-d. (Iturei Torah, Shemini Atzeret, p. 112)

One Foot
Spend one more day with me and each other. Not just yom echad, one more day, but regel achat, one foot.

Two feet are necessary to maintain balance. The body is constantly being pulled in different directions, and the feet shift minutely to maintain a constant, delicate balance. The two-foot stance represents multiple people with multiple agendas, each adjusting their agenda to accommodate the desires of others. It is a constant and delicate balancing act.

One foot, however, cannot maintain that kind of balance. It can support a single, unified body. G-d wanted this one day to be a one-foot stand for the Jewish people. Don’t pull back from your concerns to focus on another’s concern. Just dwell in your inherent oneness.

Take on the regel achat attitude on this one day. Then, when you return to your individual homesteads, the two-foot stance will come more naturally to you.

The Schedule
This is intuitive since Shemini Atzeret comes as a follow-up to Yom Kippur and Sukkot. Yom Kippur is certainly the festival of one. The one high priest, the worthiest person in the nation, entered the one Holy of Holies, the holiest place in the world, on achat bashanah, the one day in the year.

On Sukkot, our sages tell us (Sukkah 27b) that all Jews are worthy of sharing a sukkah achat, a single Sukkah. In the current age, this is infeasible. However, when the Mashiach comes, we will, in fact, be seated in a single Sukkah (Torat Menachem, Sefer Hamaamarim Melukat:1, p. 144).

There is a beautiful progression here: the one day in the year, the one Sukkah in the world, and finally, the one nation on earth.

Conclusion
We now understand Hillel’s answer. If you want to sum up the Torah, the teaching, of Shemini Atzeret, do it with the golden rule. Practice unity and love. Don’t do unto others what you don’t want done unto you.

This is the secret of this one-day festival. It commemorates something fundamental to all of Judaism. Without each other, we are useless. With each other, we are one; we are strong, and we are with G-d.

Shemini Atzeret is not a throwaway holiday. It is not just a placeholder between Sukkot and the festive Simchat Torah. It is the holiday of the year. On this day, we are empowered to overcome long-held grudges, let go of long-fought feuds, and bond with one another in the deepest ways.

It is only fitting that in the days leading up to this festival, we spend some time contemplating creative ways to make this holiday a resounding success. It is fitting that on this day we gather with others and spend time together in unity and joy. For when the Jewish people are like one, the One G-d fills our homes with blessings.