Exodus 29:9
And you shall gird them with girdles, Aaron and his sons, and put the bonnets on them: and the priest's office shall be theirs for a perpetual statute: and you shall consecrate Aaron and his sons.
Torrey's Topical Textbook—AKJV

Exodus 40:15
And you shall anoint them, as you did anoint their father, that they may minister to me in the priest's office: for their anointing shall surely be an everlasting priesthood throughout their generations.
Torrey's Topical Textbook—AKJV