Leviticus 16:33-34

International Children’s Bible

³³ He must make the Most Holy Place ready for service to the Lord. He must make the Meeting Tent and the altar ready for service to the Lord. He must remove the sins of himself and all the people of Israel so they will belong to the Lord. ³⁴ That law for removing the sins of the Israelites so they will belong to the Lord will continue forever. You will do these things once a year.”

So they did the things the Lord had commanded Moses.