Leviticus 6:1-11, from Parshat Tsav.
The Lord spoke to Moses, saying: Command Aaron and his sons thus: This is the ritual of the burnt offering: The burnt offering itself shall remain where it is burned upon the altar all night until morning, while the fire on the altar is kept going on it. The priest shall dress in linen raiment, with linen breeches next to his body; and he shall take up the ashes to which the fire has reduced the burnt offering on the altar and place them beside the altar.
He shall then take off his vestments and put on other vestments, and carry the ashes outside the camp to a clean place. The fire on the altar shall be kept burning, not to go out: every morning the priest shall feed wood to it, lay out the burnt offering on it, and turn into smoke the fat parts of the offerings of well-being. A perpetual fire shall be kept burning on the altar, not to go out.
And this is the ritual of the meal offering: Aaron's sons shall present it before the Lord, in front of the altar. A handful of the choice flour and oil of the meal offering shall be taken from it, with all the frankincense that is on the meal offering, and this token portion shall be turned into smoke on the altar as a pleasing odor to the Lord. What is left of it shall be eaten by Aaron and his sons; it shall be eaten as unleavened cakes, in the sacred precinct; they shall eat it in the enclosure of the Tent of Meeting.
It shall not be baked with leaven; I have given it as their portion from My offerings by fire; it is most holy, like the sin offering and the guilt offering. Only the males among Aaron's descendants may eat of it, as their due for all time throughout the ages from the Lord's offerings by fire. Anything that touches these shall become holy.