Leviticus 6:12-14

New King James Version

¹² And the fire on the altar shall be kept burning on it; it shall not be put out. And the priest shall burn wood on it every morning, and lay the burnt offering in order on it; and he shall burn on it ^(A)the fat of the peace offerings. ¹³ A fire shall always be burning on the ^(B)altar; it shall never go out.

The Law of the Grain Offering

¹⁴ ‘This is the law of the grain offering: The sons of Aaron shall offer it on the altar before the Lord.