Leviticus 23:26

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

25You shall do no regular work. You shall offer an offering made by fire to the LORD.’”

26The LORD spoke to Moses, saying,

27“However on the tenth day of this seventh month is the day of atonement. It shall be a holy convocation to you. You shall afflict yourselves and you shall offer an offering made by fire to the LORD.

28You shall do no kind of work in that same day, for it is a day of atonement, to make atonement for you before the LORD your God.