Leviticus 23:36-39

For seven days you must present special gifts to the LORD. The eighth day is another holy day on which you present your special gifts to the LORD. This will be a solemn occasion, and no ordinary work may be done that day. (“These are the LORD’s appointed festivals. Celebrate them each year as official days for holy assembly by presenting special gifts to the LORD—burnt offerings, grain offerings, sacrifices, and liquid offerings—each on its proper day. These festivals must be observed in addition to the LORD’s regular Sabbath days, and the offerings are in addition to your personal gifts, the offerings you give to fulfill your vows, and the voluntary offerings you present to the LORD.) “Remember that this seven-day festival to the LORD—the Festival of Shelters—begins on the fifteenth day of the appointed month, after you have harvested all the produce of the land. The first day and the eighth day of the festival will be days of complete rest.