G-d tells Moses the duties of the Kohanim and instructs him to tell Aaron and his sons.
The alter fire must burn day and night. Fat from the guilt, peace, and sin offerings and a part of the meal offering that has been separated are to be completely consumed by the fire.
Meat from the guilt and sin offerings and the remainder of the meal offering can be eaten by the Kohanim. Those who bring the peace offerings are to eat them but reserve some for the Kohanim. The offerings must be consumed by those who are ritually pure in a designated area and time.
While Moses initiates Aaron and his sons into priesthood, they are to remain in the sanctuary for a week.