This reading is from the Torah portion read on Yom Kippur. The complete reading for Yom Kippur is Leviticus 16:1-34 and Numbers 29:7-11.
And Aaron shall go into the Tent of Meeting, take off the linen vestments that he put on when he entered the Shrine, and leave them there. He shall bathe his body in water in the holy precinct and put on his vestments; then he shall come out and offer his burnt offering and the burnt offering of the people, making expiation for himself and for the people. The fat of the sin offering he shall turn into smoke on the altar.
He who set the Azazel-goat free shall wash his clothes and bathe his body in water; after that he may reenter the camp.
The bull of sin offering and the goat of sin offering whose blood was brought in to purge the Shrine shall be taken outside the camp; and their hides, flesh, and dung shall be consumed in fire. He who burned them shall wash his clothes and bathe his body in water; after that he may re-enter the camp.