John Gill's  Exposition of the Bible 

1 Kings 18:38

Then the fire of the LORD fell, and consumed the burnt sacrifice, and the wood, and the stones, and the dust, and licked up the water that was in the trench.

Then the fire of the Lord fell,.... An extraordinary fire from God out of heaven, as the effects of it show:

and consumed the burnt sacrifice; as it had done in former instances, Leviticus 9:24, and besides this, which is still more extraordinary,

and the wood, and the stones, and the dust; of the altar, thereby signifying that even such were not to be used any more:

and licked up the water that was in the trench; around the altar, see

1 Kings 18:32.