Leviticus 23:26-32

Then the LORD said to Moses, “Be careful to celebrate the Day of Atonement on the tenth day of that same month—nine days after the Festival of Trumpets. You must observe it as an official day for holy assembly, a day to deny yourselves and present special gifts to the LORD. Do no work during that entire day because it is the Day of Atonement, when offerings of purification are made for you, making you right with the LORD your God. All who do not deny themselves that day will be cut off from God’s people. And I will destroy anyone among you who does any work on that day. You must not do any work at all! This is a permanent law for you, and it must be observed from generation to generation wherever you live. This will be a Sabbath day of complete rest for you, and on that day you must deny yourselves. This day of rest will begin at sundown on the ninth day of the month and extend until sundown on the tenth day.”