Exodus 29:7-9

Modern English Version

⁷ Then shall you take the anointing oil and pour it on his head and anoint him. ⁸ You shall bring his sons and put tunics on them. ⁹ You shall gird them with sashes, Aaron and his sons, and put the headbands on them, and the priest’s office shall be theirs for a perpetual statute.

Thus you shall consecrate Aaron and his sons.