75 Elijah himself too, that the word spoken by his mouth might be confirmed, was sent by the Lord to hide himself by the brook Cherith. Ahab threatened, Jezebel threatened, Elijah was afraid and rose up, and then “went in the strength of that spiritual meat forty days and forty nights unto Horeb the mount of God;” and entered into a cave and rested there; and afterwards was sent to anoint kings. He was then inured to patience by dwelling in solitude, and, as though fed to the fatness of virtue by the homely food, went on more strong.
Source: Letters (New Advent)