21 They went to Capernaum, and when the Sabbath came, Jesus went into the synagogue and began to teach. 22 The people were amazed at his teaching, because he taught them as one who had authority, not as the teachers of the law. 23 Just then a man in their synagogue who was possessed by an evil spirit cried out, 24 "What do you want with us, Jesus of Nazareth? Have you come to destroy us? I know who you are—the Holy One of God!" 25 "Be quiet!" said Jesus sternly. "Come out of him!" 26 The evil spirit shook the man violently and came out of him with a shriek. 27 The people were all so amazed that they asked each other, "What is this? A new teaching—and with authority! He even gives orders to evil spirits and they obey him." 28 News about him spread quickly over the whole region of Galilee. 29 As soon as they left the synagogue, they went with James and John to the home of Simon and Andrew. 30 Simon's mother-in-law was in bed with a fever, and they immediately told Jesus about her. 31 So he went to her, took her hand and helped her up. The fever left her and she began to wait on them.
John Calvin abridged: The devil's acknowledgement that Christ is "the Holy One of God" was given in order to arouse suspicion in peoples' minds that the devil and Christ were allied. This happens in our own day, and is the reason Christ rebuked him. While he flatters Christ, he also withdraws from Christ. The devil cannot resist the power of Christ, so he would like to give Christ an empty title. "They were astonished at his teaching" means that the power of the Spirit shone in the preaching of Christ so that even those who were irreligious and cold admired him. His teaching was full of majesty and unlike that of other teachers. Other teacher's doctrine was literal and dead- breathing nothing of the power of the Spirit. Paul rightly says the kingdom of God is not in word but in power (1 Cor. 4:20). The title "Holy One of God" was probably in general use and given to distinguish the Messiah from all others as someone endued with grace and Head of the Church. The devil came out of him violently but Luke indicates he did not hurt him. The people were compelled to acknowledge that there is in Christ something more than ordinary humanity. They correctly race the glory and power of the miracle to his teaching. The people call it a "new doctrine" not to deride it, but to point out this teaching is unusual and extraordinary. Their only fault is that they remain in their state of hesitation instead of growing in faith.
Thought: The spiritual world is continually pointing out the divinity of Christ in Mark. For example, the voice from heaven at the baptism and configuration as well as this demon. Capernaum became Jesus' home (Mt. 4:13) and base of ministry. He established his base first by driving out evil and sickness- so the people would see He has come in power to help them. Today, too many see Christianity as basically a dead philosophy with no real power to help. It is almost as if they turn away from the power of Christ because it scares them, or they simply do not want to believe in such a power. Christ is not dead but alive.
Prayer: May your power live in me. Cleanse me of evil and use me to further your work of cleansing this world of evil.