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 23:27-32

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.
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 jshall be cut off from his people. 30And whoever does any work on that very day, that person I will destroy from among his people. 31You shall not do any work. It is a statute forever throughout your generations in all your dwelling places. 32It shall be to you a Sabbath of solemn rest, and you shall afflict yourselves. On the ninth day of the month beginning at evening, from evening to evening shall you keep your Sabbath.”

Jeremiah 36:9

9 kIn the fifth year of Jehoiakim the son of Josiah, king of Judah, lin the ninth month, all the people in Jerusalem and all the people who came from the cities of Judah to Jerusalem mproclaimed a fast before the Lord.

Acts 27:9

9Since much time had passed, and the voyage was now dangerous because even nthe Fast
That is,  the Day of Atonement
was already over, Paul advised them,
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