In rapid fire succession Mark gives us story after story of Jesus' miracles. He shows Jesus' authority over nature (in the boat) and now tells a story of Jesus' authority over the spiritual realm. In ancient times it was standard practice to identify the spirit before casting it out and here we see the spirit in the demon possessed man actually trying to go up against Jesus. When He sees Jesus he approaches and names Jesus telling Him he had no business there. The spirit even tries to use the only authority higher than Jesus to do it, he says, "What do you want with me, Jesus, Son of God? (Identification) In God's name (higher authority) don't torture me!"
Jesus, with all the authority of the Father at His disposal, commands the demons to leave the man and gives them permission to go into the pigs.
God (Jesus) is powerful and mighty. He has authority over everything. We need not fear because we are God's children and He has the power and ability to keep us and protect us. The sad part of this story is that the people let fear and economics push Jesus away instead of embracing Him. The one who is the most powerful and can protect us we push away in fear.
Psalm 20:7 (NIV) 7 Some trust in chariots and some in horses, but we trust in the name of the LORD our God.
Here's a song that talks about the power of our God.
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