Leviticus 23:33-36

33 Feast of Tabernacles
The Lord said to Moses,

34 “Say to the Israelites: ‘On the fifteenth day of the seventh month the Lord’s Feast of Tabernacles begins, and it lasts for seven days.

35 The first day is a sacred assembly; do no regular work.

36 For seven days present offerings made to the Lord by fire, and on the eighth day hold a sacred assembly and present an offering made to the Lord by fire. It is the closing assembly; do no regular work.