Chol HaMoed
The second through seventh days of Sukkot (third through seventh days outside Israel) are called Chol HaMoed (חול המועד - lit. "festival weekdays"). These days are considered by halakha to be more than regular weekdays but less than festival days. In practice, this means that all activities that are needed for the holiday—such as buying and preparing food, cleaning the house in honor of the holiday, or traveling to visit other people's sukkot or on family outings—are permitted by Jewish law. Activities that will interfere with relaxation and enjoyment of the holiday—such as laundering, mending clothes, engaging in labor-intensive activities—are not permitted. Observant Jews typically treat Chol HaMoed as a vacation period, eating nicer than usual meals in their sukkah, entertaining guests, visiting other families in their sukkot, and taking family outings. Many synagogues and Jewish centers also offer events and meals in their sukkot during this time to foster community and goodwill.
On the Shabbat which falls during the week of Sukkot (or in the event when the first day of Sukkot is on Shabbat), the Book of Ecclesiastes is read during morning synagogue services in Israel. (Diaspora communities read it the following Shabbat). This Book's emphasis on the ephemeralness of life ("Vanity of vanities, all is vanity...") echoes the theme of the sukkah, while its emphasis on death reflects the time of year in which Sukkot occurs (the "autumn" of life). The second-to-last verse reinforces the message that adherence to God and His Torah is the only worthwhile pursuit. Ecclesiastes 12:13,14
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