Leviticus 6:12-14

12The fire on the altar shall be kept burning on it. It shall not go out, but the priest shall burn wood on it every morning; and he shall lay out the burnt offering on it, and offer up in smoke the fat portions of the peace offerings 1on it. 13Fire shall be kept burning continually on the altar; it is not to go out.

14‘Now this is the law of the grain offering: the sons of Aaron shall present it before the Lord in front of the altar.