Exodus 40:15

15 Anoint them just as you anointed their father, so that they may also serve Me as priests. Their anointing will serve to inaugurate a permanent priesthood for them throughout their generations."

Exodus 40:15 Meaning and Commentary

Exodus 40:15

And thou shall anoint them as thou didst anoint their
father
For Aaron was first anointed, and then his sons:

that they may minister unto me in the priest's office;
which they might not do before their anointing, though separated for it, and called unto it:

for their anointing shall surely be an everlasting priesthood
throughout their generations;
that is, this ceremony of anointing was to be used in all ages at the investiture of the high priest with his office, until the Messiah should come, who would put an end to the Aaronic priesthood; for not common priests, only the successors of the high priest, were anointed in later times; this present unction serving for all the priests that should follow in successive generations, so long as the priesthood continued.

Exodus 40:15 In-Context

13 Clothe Aaron with the holy garments, anoint him, and consecrate him, so that he can serve Me as a priest.
14 Have his sons come forward and clothe them in tunics.
15 Anoint them just as you anointed their father, so that they may also serve Me as priests. Their anointing will serve to inaugurate a permanent priesthood for them throughout their generations."
16 Moses did everything just as the Lord had commanded him.
17 The tabernacle was set up in the first month of the second year, on the first [day] of the month.