Rabbinic tradition teaches that on Shemini Atzeret the world is judged for water, or rainfall, in the upcoming year. In an agricultural society it was a very important day. Water continues to be a chief concern of ours, especially in Israel, where the water supply is dangerously low. Israel is among the world's nations listed as experiencing water scarcity. Recent plans to remedy the situation involve purchasing vast amounts of water from other countries. On Shemini Atzeret we recite special prayers asking for rain.

In addition to the agricultural significance of the holiday, there are many other explanations given for the Shemini Atzeret in Rabbinic literature. Shemini Atzeret is understood as a day highlighting the special relationship between the Jewish people and God. Another explanation focuses on Shemini Atzeret's coming at the end of a particularly rich holiday season. During the Hebrew month of Tishrei we celebrate Rosh Hashana, which is followed ten days later by Yom Kippur. Five days later comes Sukkot. A midrash says that on Shemini Atzeret God says to the Jewish people,"your departure is difficult for me. Stay with me one more day."

Simchat Torah is celebrated the same day as Shemini Atzeret in Israel and by Reform Jews. Outside of Israel, where Jewish legal tradition requires that two days be kept, Simchat Torah occurs on the day following Shemini Atzeret. On Simchat Torah we celebrate the completion of the yearly cycle of Torah reading and begin it anew. We mark our celebration by dancing and singing with the Torah. Communities that observe a triennial cycle - i.e. they complete reading the Torah every three years - nonetheless celebrate Simchat Torah each year. In order to celebrate the Torah and every Jew's relationship to it, there is a tradition that everyone is called up the Torah on Simchat Torah to recite the Torah blessings.