Leviticus 16:20-34
"And when he has made an end of atoning for the holy place and the tent of meeting and the altar, he shall present the live goat; and Aaron shall lay both his hands upon the head of the live goat, and confess over him all the iniquities of the people of Israel, and all their transgressions, all their sins; and he shall put them upon the head of the goat, and send him away into the wilderness by the hand of a man who is in readiness. The goat shall bear all their iniquities upon him to a solitary land; and he shall let the goat go in the wilderness.
"Then Aaron shall come into the tent of meeting, and shall put off the linen garments which he put on when he went into the holy place, and shall leave them there; and he shall bathe his body in water in a holy place, and put on his garments, and come forth, and offer his burnt offering and the burnt offering of the people, and make atonement for himself and for the people. And the fat of the sin offering he shall burn upon the altar. And he who lets the goat go to Aza'zel shall wash his clothes and bathe his body in water, and afterward he may come into the camp. And the bull for the sin offering and the goat for the sin offering, whose blood was brought in to make atonement in the holy place, shall be carried forth outside the camp; their skin and their flesh and their dung shall be burned with fire. And he who burns them shall wash his clothes and bathe his body in water, and afterward he may come into the camp.
"And it shall be a statute to you for ever that in the seventh month, on the tenth day of the month, you shall afflict yourselves, and shall do no work, either the native or the stranger who sojourns among you; for on this day shall atonement be made for you, to cleanse you; from all your sins you shall be clean before the LORD. It is a sabbath of solemn rest to you, and you shall afflict yourselves; it is a statute for ever. And the priest who is anointed and consecrated as priest in his father's place shall make atonement, wearing the holy linen garments; he shall make atonement for the sanctuary, and he shall make atonement for the tent of meeting and for the altar, and he shall make atonement for the priests and for all the people of the assembly. And this shall be an everlasting statute for you, that atonement may be made for the people of Israel once in the year because of all their sins." And Moses did as the LORD commanded him.