Elijah has had a good run, literally and figuratively.
He has decimated Queen Jezebel's religious community by personally executing her four hundred prophets of Baal in 1 Kings 18:40. That he neither executed nor challenged her four hundred and fifty prophets of Asherah, (see verse 19ff), points to a broader acceptance of the Asherah tradition.
While the prophets uniformly condemn the worship of Baal, many are silent on the worship of Asherah regarded as complimentary to and not as competitive with the God of Israel. Isaiah only has two references to her, while Jeremiah and Micah have just one reference each. (Compare that to Jeremiah's ten references against Baal worship.) Hosea and Zephaniah both mention Baal worship, but not Asherah worship. The prophets who do not condemn the worship of Asherah at all include Ezekiel, who condemns the worship of other deities in the temple, Joel, Amos, Obadiah, Jonah, Nahum, Habakkuk, Haggai, Zechariah and Malachi.
As a result Elijah's actions, to mix metaphors, Jezebel has demanded Elijah's head on a platter. Elijah has fled to where he imagines he will be beyond Jezebel's grasp. He is safe for the moment, but he is anything but secure. God has provided him divine comfort and companionship along his journey and actual, edible food and potable water with supernatural benefits, (1 Kings 19:5-8). Elijah is sustained by his meal(s) for an unimaginably long time. ("Forty days and forty nights" is a euphemism for "a really long time." It is no more a mathematical formula than is "a month of Sundays.")
Passing through Beer-Sheba, as the crow flies, the Kishon wadi, (the site of the execution) is some 300 miles northwest of the mountain range home to the "mountain of God" called Sinai in some traditions and Horeb in this story. Traveling twenty miles or so a day (or night) and avoiding anyone who might have turned him in would have taken weeks -- two at breakneck speed, likely more at his pace. Elijah's pace would also have been affected by whether or not he was mounted for all or part of the journey; the text suggests but does not specify that he was not. No mount is mentioned.
Sometime after Elijah falls asleep, God speaks to him, questioning him. What is he doing here? God is not always omniscient in the bible; that is a later theological claim. (God asks Adam, where he is and who told him he was naked and had he been eating the forbidden fruit in Genesis 2. In other places God knows what is in the human heart, see Genesis 6:5; 1 Kings 8:39; Psalm 44:21, etc.) As Elijah catches God up on recent events from his perspective, it is not immediately clear whether God's questions are informational or rhetorical. What Elijah does not say is that he is hiding from Jezebel or that he has come to seek God's help and protection.
God responds to Elijah's self-assessment with self-revelation. First God displayed historic and traditional signs of God's presence, a windstorm, an earthquake and fire (from heaven?). But God was not present among the usual suspects. Then there was a qol dammah daqah, a sound (or voice) of a fine silence. And that is where Elijah encountered God.
While Elijah encountered God-in-silence on a revered mountain, it strikes me that the setting was not necessary for the encounter. That was where Elijah was at the time. The divine appearance was not dependant on an indigenous feature, such as the bush that burned and was not consumed. Perhaps Elijah could have encountered God-in-silence at any point along his journey and even without taking a single step.
After his epiphany, God asks Elijah the same question that God asked him before. Now it is clear that this is a rhetorical question. Elijah gives essentially the same answer. His experience with God has not changed him. I think this is an important observation for contemporary readers and hearers of the scriptures who would like to imagine ourselves in the sacred stories. I know that I have thought how different my own faith story would have been had I been able to see, hear and experience what my spiritual ancestors saw, heard and experienced.
The story of Elijah says, not so fast. Elijah saw, heard and experienced God in fantastic ways. The power of God flowed through him to work miracles that were unequalled by anyone before him. Yet Elijah was essentially unchanged by this incredible encounter with God. And so God fired him, or at least announced his retirement. It is hard to know how Elijah heard the command to anoint another prophet to take his place in verse 16. It may have been quite troubling because the monarchs whom God was firing/retiring/replacing, Ben-Hadad of Aram and Ahab of Israel (who are not named in the text) were to be killed. There was no other retirement plan for kings.
God's last words to Elijah are that God does not need Elijah; God has untold thousands-upon-thousands (seven thousand is a figurative number) of faithful servants on whom God can depend. What is missing from the assigned lesson is Elijah's response. He accepts his assignment from God, knowing that his time as God's prophet is drawing to an end, not knowing what that end will be.
Elijah faithfully calls Elisha whom God has designated as his successor in the verses following the lesson. Hazael will assassinate Ben-Hadad in 2 Kings 8:15 and succeed him; it is not clear if Elijah (or Elisha) ever actually anointed him. And Elisha will complete Elijah's work and anoint Jehu in 2 Kings 9. (Ahab dies in battle, 1 Kings 22:20ff.) And along the way, God reveals a spectacular retirement plan for Elijah in 2 Kings 2:11, towards which Elijah journeys faithfully, not knowing the outcome.