Leviticus 16:29-30

And {this} shall be a statute for ever unto you: {that} in the seventh month, on the tenth {day} of the month, ye shall afflict your souls, and do no work at all, {whether it be} one of your own country, or a stranger that sojourneth among you: For on that day shall {the priest} make an atonement for you, to cleanse you, {that} ye may be clean from all your sins before the LORD.