Leviticus 23:40-43

23:40 On the first day you must take for yourselves branches from majestic trees – palm branches, branches of leafy trees, and willows of the brook – and you must rejoice before the Lord your God for seven days. 23:41 You must celebrate it as a pilgrim festival to the Lord for seven days in the year. This is a perpetual statute throughout your generations; you must celebrate it in the seventh month. 23:42 You must live in temporary shelters for seven days; every native citizen in Israel must live in temporary shelters, 23:43 so that your future generations may know that I made the Israelites live in temporary shelters when I brought them out from the land of Egypt. I am the Lord your God.’”