Fire came down from heaven on Mount Carmel and everyone was on their knees, but yet there was no revival. Because of this, Elijah was depressed to the point of desiring death. His mission seemed a failure.
God brought Elijah to Mount Horeb (Mount Sinai) and had a surprising revelation for Elijah (and us). Wind, fire and earthquake came, but God was not in the wind, he was not in the fire, and he was not in the earthquake. God instead revealed himself as a still, small and gentle voice. The meaning of this revelation to Elijah is one of the most profound messages in the entire Old Testament.