Leviticus 6:13-15

New King James Version

¹³ A fire shall always be burning on the ^(A)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. ¹⁵ He shall take from it his handful of the fine flour of the grain offering, with its oil, and all the frankincense which is on the grain offering, and shall burn it on the altar for a sweet aroma, as a memorial to the Lord.