Leviticus 16:29-31

29“And it shall be a statute to you forever that ain the seventh month, on the tenth day of the month, you shall bafflict yourselves
Or  shall fast; also verse 31
and shall do no work, either dthe native or the stranger who sojourns among you.
30For on this day shall atonement be made for you eto cleanse you. You shall be clean before the Lord from all your sins. 31 fIt is a Sabbath of solemn rest to you, and you shall gafflict yourselves; it is a statute forever.

Leviticus 23:27

27Now hon 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.
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