Charles Ellicott Commentary Leviticus 9:24

"And there came forth fire from before Jehovah, and consumed upon the altar the burnt-offering and the fat: and when all the people saw it, they shouted, and fell on their faces." — Leviticus 9:24 (ASV)

And there came a fire.—As a further indication of His acceptance of all the previously mentioned rites, the Lord sent forth from the luminous cloud flashes of fire, which, on this occasion, suddenly consumed in the sight of the people the victims that ordinarily continued smoldering on the altar all day and all night. In this manner God afterwards testified His acceptance of the sacrifice of Gideon (Judges 6:20–21), of Elijah (1 Kings 18:28), and of the sacrifices of Solomon at the dedication of the Temple (2 Chronicles 7:1–2). Tradition assures us that the sacred fire which thus issued forth from the immediate presence of God continued to be nourished on the altar with the fuel especially provided by the congregation, and constituted the perpetual fire .

They shouted, and fell on their faces.—On seeing these visible tokens of the Divine acceptance of the services, the people expressed their thankfulness in the same way they showed it on a similar occasion. Thus we are told—When all the sons of Israel saw how the fire came down, and the glory of the Lord shone upon the house, they bowed themselves with their faces to the ground upon the pavement, and worshipped and praised the Lord, saying, For he is good, for his mercy endureth for ever (2 Chronicles 7:3).