Leviticus 23:37-40

37(“ ‘These are the Lord’s appointed festivals, which you are to proclaim as sacred assemblies for bringing food offerings to the Lord—the burnt offerings and grain offerings, sacrifices and drink offerings required for each day.

38These offerings are in addition to those for the Lord’s Sabbaths and in addition to your gifts and whatever you have vowed and all the freewill offerings you give to the Lord.)

39“ ‘So beginning with the fifteenth day of the seventh month, after you have gathered the crops of the land, celebrate the festival to the Lord for seven days; the first day is a day of sabbath rest, and the eighth day also is a day of sabbath rest.

40On the first day you are to take branches from luxuriant trees—from palms, willows and other leafy trees—and rejoice before the Lord your God for seven days.