Leviticus 1:7

1:7 and the sons of Aaron, the priest, must put fire on the altar and arrange wood on the fire.

Leviticus 6:13

6:13 A continual fire must be kept burning on the altar. It must not be extinguished.

Leviticus 10:2

10:2 So fire went out from the presence of the Lord and consumed them so that they died before the Lord.