Once upon a time in a faraway kingdom, there lived an evil queen named Jezebel and her childish husband, Ahab. They led their people to worship heathen gods, and murdered any prophet of the Lord that they could get their hands on. Without heavenly guidance, their people were led into idolatry and wickedness. Then one day, a wizard with a feral look in his eye rode into town on the road from Gilead, trailing a storm that would topple the despicable regime of Ahab and Jezebel forever.
That wizard, of course, is Elijah. In our opinion, he's one of the coolest figures in all of Bible-dom. His story is so larger-than-life, it doesn't even all fit into 1st Kings, so we'll have to stray a bit into 2nd Kings to tell it. Other than maybe Moses, nobody else compares when it comes to power, cantankerousness, and (strangely) holiness. If Moses fills the Obi-Wan Kenobi/Elrond/Dumbledore role, then Elijah is the Yoda/Gandalf/Snape character.
He's gruff (18:17-18), bold (18:9-24), hairy (2 Kings 1:8), angry (18:21), and violent (18:40). But he's also humble (19:4), compassionate (17:20-21), devout (his name means "My God is Yahweh"), prophetic (21:20-21), and attuned with nature (18:41-46). Oh, and he's basically a nigh omnipotent elemental mage.
Elijah has some kind of connection to the natural world and its constituents. He survives an earthquake/fire/windstorm without a scratch on him (19:11-13). Ravens (17:6), storm clouds (17:1), and fire (18:37-38) obey him. He can even somehow manipulate matter, presumably on a molecular level, to create endless supplies of food (17:13-16). And that's not even the craziest part. He even has power over death. Not only does he raise a kid from the dead (17:17-22), but he's also one of only a handful characters in the whole Bible that never dies. At all. The guy never dies. In the next book, instead of succumbing to the circle of life, he rides either (A) a whirlwind, (B) a chariot of fire, or (C) both—straight up to heaven (2nd Kings 2:11).
With powers like these, it's not surprising that he don't take no flapdoodle from nobody. When Jezebel hires a bunch of priests to officiate over her sleazy Baal worship, he challenges all 850 of them to basically a wizard's duel by himself. He wins and kills them all, natch (18:40). Ahab and Jezebel are gunning for him from then on, but he still just walks right into Ahab's backyard to tell him that the Lord's going to kill him and feed his blood to dogs. And in the 2nd Kings, when Ahaziah sends his armies to capture him, Elijah kills 102 soldiers with fire from heaven (2nd Kings 1:9-12). Do. Not. Mess. With Elijah.
Of course, these powers aren't really his, per se. God gives them to him because of his uncommon faithfulness (19:14). In fact, while you're reading about Elijah, you might recognize a lot of things that his story has in common with the story of Jesus Christ in the New Testament: in addition to raising the dead (see John 11:41-44); miraculously multiplying food (see Matthew 15:32-38); ascending into heaven (see Acts 1:9-10); and controlling the weather (see Mark 4:39), Elijah also fasts for fourty days and fourty nights (see 18:8; Matthew 4:2); is strengthened by angels (see 18:5-7; Luke 22:43); and, oh yeah, he not only appears after his "death" (see Matthew 17:3; Luke 24:34-36), but is prophesied to come to earth again later in the Hebrew Bible (see Malachi 4:5; Acts 1:11). Given these similarities to one of history's biggest religious superstars, to say that Elijah is a spiritual guy would be an understatement.
It's no wonder that he's held in such high esteem by various religious traditions. He's a towering mega-prophet whose unique mix of holiness and true grit means we'd follow him into battle any day, and he's the last guy we'd ever want to cross. He's like God's Boba Fett.
(By the way, his apprentice, Elisha [see 19:19-21], is pretty dang hardcore as well. That's what happens when you're trained by the best.)