Leviticus 16:29-34

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. It shall be a sabbath of rest unto you, and ye shall afflict your souls, by a statute for ever. And the priest, whom he shall anoint, and whom he shall consecrate to minister in the priest's office in his father's stead, shall make the atonement, and shall put on the linen clothes, even the holy garments: and he shall make an atonement for the holy sanctuary, and he shall make an atonement for the tabernacle of the congregation, and for the altar, and he shall make an atonement for the priests, and for all the people of the congregation. And this shall be an everlasting statute unto you, to make an atonement for the children of Israel for all their sins once a year. And he did as the LORD commanded Moses.