On the day they were anointed, the LORD commanded that this be given them by the sons of Israel. It is a permanent portion for the generations to come.

Exodus 40:13
And you are to clothe Aaron with the holy garments, anoint him, and consecrate him, so that he may serve Me as a priest.

Leviticus 3:17
This is a permanent statute for the generations to come, wherever you live: You must not eat any fat or any blood."

Leviticus 8:12
He also poured some of the anointing oil on Aaron's head and anointed him to consecrate him.

Leviticus 8:30
Next, Moses took some of the anointing oil and some of the blood that was on the altar and sprinkled them on Aaron and his garments, and on his sons and their garments. So he consecrated Aaron and his garments, as well as Aaron's sons and their garments.

1 Samuel 2:28
And out of all the tribes of Israel I selected your father to be My priest, to offer sacrifices on My altar, to burn incense, and to wear an ephod in My presence. I also gave to the house of your father all the offerings of the Israelites made by fire.

Which the LORD commanded to be given them of the children of Israel, in the day that he anointed them, by a statute for ever throughout their generations.