"And as he lay and slept under a juniper tree, behold, then an angel touched him, and said unto him, Arise and eat. And he looked, and, behold, there was a cake baken on the coals, and a cruse of water at his head. And he did eat and drink, and laid him down again. And the angel of the LORD came again the second time, and touched him, and said, Arise and eat; because the journey is too great for thee."
Elijah displayed great courage in confronting hundreds of false prophets on Mt. Carmel. God sent fire from Heaven to consume the sacrifice on the altar Elijah built, providing a display of divine power to confirm that Elijah was speaking truth when he declared that Jehovah was the only true God. Yet following that great victory, Elijah fell into despair. He heard that Jezebel was trying to kill him, and he ran into the desert alone. But even when no one was around, God still knew where His discouraged prophet was, and came to help him. When the Bible speaks of “the angel of the LORD,” it is speaking of a pre-incarnate appearance of Jesus.
The Lord Himself came to Elijah, gave him something to eat and drink, and let him rest. He knew what He had in store for the prophet, and He knew that the tasks could not be accomplished in Elijah's own strength and resources—he needed divine help.
Similarly, in the Upper Room, Jesus told the disciples, “I am the vine, ye are the branches: He that abideth in me, and I in him, the same bringeth forth much fruit: for without me ye can do nothing” (John 15:5). God's work is beyond our ability to accomplish from our own resources. We must have His help. As the old hymn put it, “All is vain unless the Spirit of the Holy One comes down.”
Trying to work for God in our own strength is a recipe for disaster and failure. Relying on His strength is a recipe for victory.