Leviticus 23:26

Speak to the children of Israel, saying, 'In the seventh month, on the first day of the month, shall be a solemn rest to you, a memorial of blowing of trumpets, a holy convocation.

You shall do no regular work; and you shall offer an offering made by fire to Yahweh.

However on the tenth day of this seventh month is the day of atonement: it shall be a holy convocation to you, and you shall afflict yourselves; and you shall offer an offering made by fire to Yahweh.

You shall do no kind of work in that same day; for it is a day of atonement, to make atonement for you before Yahweh your God.