Leviticus 16:32-34

Living Bible

³² This ceremony, in later generations, shall be performed by the anointed High Priest, consecrated in place of his ancestor Aaron; he shall be the one to put on the holy linen garments, ³³ and make atonement for the holy sanctuary, the Tabernacle, the altar, the priests, and the people. ³⁴ This shall be an everlasting law for you, to make atonement for the people of Israel once each year, because of their sins.”

And Aaron followed all these instructions that the Lord gave to Moses.