Eliah said to Ahab, "As the Lord lives, there will be not rain"

1 Kings 17:1-7
Elijah the Tishbite, from Tishbe in Gilead, said to Ahab,"As the Lord, the God of Israel, lives, there will be neither dew or rain in the next few years except at my word."
Then the word of the Lord came to Elijah: "Leave here, turn eastward and hide in the Kerith Ravine, east of the Jordan. You will drink fro the brook, and I have ordered the ravens to feed you there."
Why?
Even Ahab forgot the name of the Lord, the Lord let Elijah showed up, let the Israelite knew that the Lord is the God of Israel. God will have drought over Israel for three years. Warning them turn to the Lord.
God let raven to feed Elijah means God will afford the living of Elijah, God's servant. So to be a servant of the Lord don't worry about the living, God can do it.
Get rid of some Baals in the world, serve the Lord wholly, God can recover all problems.
How?
Declare against the devil, for the Lord is my God, and let's my faith more stronger.