Leviticus 3:17

3:17 This is a perpetual statute throughout your generations in all the places where you live: You must never eat any fat or any blood.’”

Exodus 29:9

29:9 and wrap the sashes around Aaron and his sons and put headbands on them, and so the ministry of priesthood will belong to them by a perpetual ordinance. Thus you are to consecrate Aaron and his sons.