Leviticus 23:8, 12, 36

For seven days you must present special gifts to the LORD. On the seventh day the people must again stop all their ordinary work to observe an official day for holy assembly.”

On that same day you must sacrifice a one-year-old male lamb with no defects as a burnt offering to the LORD.

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.