What does 1 Kings 18:21-40 mean?

And Elijah came near to all the people and said, “How long will you go limping between two different opinions? If the LORD is God, follow him; but if Baal, then follow him.” And the people did not answer him a word. Then Elijah said to the people, “I, even I only, am left a prophet of the LORD, but Baal’s prophets are 450 men. Let two bulls be given to us, and let them choose one bull for themselves and cut it in pieces and lay it on the wood, but put no fire to it. And I will prepare the other bull and lay it on the wood and put no fire to it. And you call upon the name of your god, and I will call upon the name of the LORD, and the God who answers by fire, he is God.” And all the people answered, “It is well spoken.” Then Elijah said to the prophets of Baal, “Choose for yourselves one bull and prepare it first, for you are many, and call upon the name of your god, but put no fire to it.” And they took the bull that was given them, and they prepared it and called upon the name of Baal from morning until noon, saying, “O Baal, answer us!” But there was no voice, and no one answered. And they limped around the altar that they had made. And at noon Elijah mocked them, saying, “Cry aloud, for he is a god. Either he is musing, or he is relieving himself, or he is on a journey, or perhaps he is asleep and must be awakened.” And they cried aloud and cut themselves after their custom with swords and lances, until the blood gushed out upon them. And as midday passed, they raved on until the time of the offering of the oblation, but there was no voice. No one answered; no one paid attention. Then Elijah said to all the people, “Come near to me.” And all the people came near to him. And he repaired the altar of the LORD that had been thrown down. Elijah took twelve stones, according to the number of the tribes of the sons of Jacob, to whom the word of the LORD came, saying, “Israel shall be your name,” and with the stones he built an altar in the name of the LORD. And he made a trench about the altar, as great as would contain two seahs of seed. And he put the wood in order and cut the bull in pieces and laid it on the wood. And he said, “Fill four jars with water and pour it on the burnt offering and on the wood.” And he said, “Do it a second time.” And they did it a second time. And he said, “Do it a third time.” And they did it a third time. And the water ran around the altar and filled the trench also with water. And at the time of the offering of the oblation, Elijah the prophet came near and said, “O LORD, God of Abraham, Isaac, and Israel, let it be known this day that you are God in Israel, and that I am your servant, and that I have done all these things at your word. Answer me, O LORD, answer me, that this people may know that you, O LORD, are God, and that you have turned their hearts back.” Then the fire of the LORD fell and consumed the burnt offering and the wood and the stones and the dust, and licked up the water that was in the trench. And when all the people saw it, they fell on their faces and said, “The LORD, he is God; the LORD, he is God.” And Elijah said to them, “Seize the prophets of Baal; let not one of them escape.” And they seized them. And Elijah brought them down to the brook Kishon and slaughtered them there.