Leviticus 23:39-43

“ ‘So on the fifteenth day of the seventh month, after you have gathered in the crops of the land, celebrate the LORD’s festival for seven days. You must rest on the first day and the eighth day. On the first day you will take good fruit from the fruit trees, as well as branches from palm trees, poplars, and other leafy trees. You will celebrate before the LORD your God for seven days. Celebrate this festival to the LORD for seven days each year. This law will continue from now on; you will celebrate it in the seventh month. Live in shelters for seven days. All the people born in Israel must live in shelters so that all your descendants will know I made Israel live in shelters during the time I brought them out of Egypt. I am the LORD your God.’ ”