Leviticus 16:31
16:31 It is to be a Sabbath of complete rest for you, and you must humble yourselves.
It is a perpetual statute.
Leviticus 23:39
23:39 “‘On the fifteenth day of the seventh month, when you gather in the produce of the land, you must celebrate a pilgrim festival of the Lord for seven days. On the first day is a complete rest and on the eighth day is complete rest.