In this chapter, Elijah defeats the prophets of Baal and prays for the end of the drought.
This is another famous story (or at least, famous amongst the kind of people that I talk to). There are a couple big themes I want to talk about and a couple little details.
In big themes, the first I will discuss is the contrast between Baal and the LORD. In verse 21, Elijah says that the people are wavering between two opinions, but in so many ways we can see that Baal is honored over the LORD. From the royalty, we learn that Jezebel is not just a worshiper of Baal, but she is literally killing the prophets of the LORD (v. 4). And what about the people? It is likely that the people tore down the altar of the LORD (v. 30), whereas the altar of Baal remained. At both the highest and lowest levels of society, the people favored Baal over the LORD.
Besides that, there is also a contrast of strength. There are 450 prophets of Baal, and only one prophet of the LORD. Nevertheless, in spite of that we can clearly see that Elijah is in control of the situation. The prophets of Baal dance and prophesy frantically, cutting themselves to urge Baal to act, while Elijah is confident enough to mock them for their efforts. Finally, we see that it's not numbers that matter, it's not the emotional appeal that matters, it is simply a question of which of these gods is real and has real power to change the world and answer prayer. Elijah does everything he can to put himself at a disadvantage to the prophets of Baal, giving them more time to pray, more numbers, and pouring water on his own offering to prevent it (if such a thing were possible) from burning. It simply comes down to which god is God, and as the people put it, the LORD is God (v 39).
In verse 29, it says that the prophets of Baal "prophesied until the time of the evening offering", though translations of the word "prophesy" vary. I think this is interesting because of previous discussions that I've had about the interpretations of the word "naba", which means prophesy. In this case, I believe "naba" has a similar meaning to those previous situations, as the prophets of Baal wildly prophesy in their attempts to arouse Baal to action. Again, it does not mean predicting the future, it is a kind of religious ritual whose exact nature is hard to identify.
In verse 30, it says that Elijah rebuilt the altar of the LORD which had been torn down. Is it permitted to offer sacrifices on a high place, away from the temple? According to the Law, I believe the answer is no (and Rashi says something like this in his commentary). However, because Elijah was acting according to the word of the LORD, he was permitted to do so. It is unlikely the people in the northern kingdom would travel to Jerusalem when they do not worship the LORD, and they needed to see a demonstration of power in order for God to "turn their hearts back again" (v. 37).
Even if it was forbidden for Israelites to offer sacrifices on the high places (i.e. local worship venues), I feel that there is something pious about Elijah here, the lone prophet rebuilding the altar. Elijah uses 12 stones as a symbol of Israel's unity as a nation, and he offers the sacrifice at the time of the evening offering, which again shows that Elijah is consciously seeking to honor the LORD. That's the biggest takeaway that I have from Elijah's behavior in verses 30-37, is Elijah's references to the patriarchs and to God's commands to the people.
The evening offering was supposed to be burned with fire (like many offerings) on the altar in Jerusalem, so God's response was to burn the offering. In the first place, this is a miracle and demonstration of God's supremacy over Baal. In the second place, this is a sign of God's acceptance of Elijah and an acceptance of his offering. It's not just God showing his power, it's showing his power and approval of Elijah. Thirdly, God is fulfilling the ordinances by burning the offering, in accordance with the Law. It's not just God's approval of Elijah, God is implicitly endorsing the regulations of the Law of Moses by himself fulfilling part of the command to sacrifice a burnt offering at a particular time (the evening offering).
After this miracle, Elijah uses his established authority (as the people realize the supremacy of the LORD) to order the death of all the prophets of Baal. Just like Jezebel killed the prophets of the LORD, Elijah responds in kind by killing the false prophets who ate at Jezebel's table.
As a minor point, verse 12 establishes the possibility of God's spirit transporting a person from one place to another, at least in Obadiah's belief.
Lastly, Elijah tells Ahab that the drought is ended, and then he goes to pray for the end of the drought. I don't know why Elijah chose this time to end the drought. Perhaps he believed that the people were, in fact, turning back to the LORD, and wanted to end the drought as a sign of reconciliation that God would still accept them. Either way, I see this story as a powerful example of persistent prayer. Elijah had to pray seven times before he saw even a small cloud form, a very small cloud. But seeing the small cloud, Elijah knew at once that God was sending the storm he had requested.
In this same chapter, Elijah prayed once and God sent down fire from heaven to consume an offering. But in order to end the drought, Elijah needed to persist in prayer until God answered him with rain. Both fire and rain are metaphors for God's presence, and both of them require prayer. I'm not sure why it takes a single prayer or persistence, but I know that in both cases it takes faith. It takes Elijah's faith to call fire down from heaven, and it takes faith for him to remain persistent in prayer even when he wasn't seeing any results time after time. I think in both cases God was responding to Elijah's faith.
I think the lesson for us is to understand God's command ("I have done all these things at your word", v. 36) and then to pursue God's will operating in faith. Then miracles happen, whether it is the miracle of fire or rain, burning away the sins of idolatry or washing the dry land with healing waters.