Leviticus 9:23-24

23Moses and Aaron went into the Tent of Meeting. When they came out, they asked God to do good things for the people. The bright light from the Lord appeared to the people to show how great he is.

24Then the Lord sent a fire to show that he accepted the gifts. It completely burnt all the fat and the offerings that were on the altar. The people were very happy when they saw this. They shouted and they fell down with their faces to the ground.