Leviticus 23:27-29

27Now aon the tenth day of this seventh month is the Day of Atonement. It shall be for you a time of holy convocation, and you shall afflict yourselves
Or  shall fast; also verse 32
and present a food offering to the Lord.
28And you shall not do any work on that very day, for it is a Day of Atonement, to make atonement for you before the Lord your God. 29For whoever is not afflicted on that very day cshall be cut off from his people.
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