Four of Christ's thirty-three miracles concern the casting out of demons. Satan always tries to counter God's work, and thus the years surrounding Jesus' ministry saw a marked rise in demonic activity. Scripture shows that exposing and casting out Satan and his demons is the responsibility of Christ (I John 3:8).
Evidently, some demons crave embodiment, and so demon possession consists of one or more demons inhabiting a human or even animals (Luke 8:32-33). Mental diseases, with their erratic or even insane behavior, along with physical diseases, often accompany demon-possession, for demons perversely desire to destroy even the bodies they inhabit.
The exorcism in the synagogue (Mark 1:21-28; Luke 4:31-37) occurs on a busy day for Jesus. He teaches in the synagogue, casting out a demon there. He then goes to Peter's house to heal his mother-in-law. Later in the evening, the whole city gathers at Peter's door, where "they brought to Him all who were sick and those who were demon-possessed" (Mark 1:32). All this activity shows His power over demons and great compassion for the people.
1. Why are demons called "unclean spirits"? Mark 1:23, 26.
Comment: Mark calls the usurping demon "unclean," indicating moral impurity. It is also a troublemaker, as seen in its contrary attitude. It is interesting that the demon violently recoils when faced with the authority of the spiritually clean Christ. Recognizing His holiness and unwilling to remain in Jesus' presence, it cries out in fear.
We see a similar uncleanness in those who trouble a congregation; they invariably live spiritually impure lives. They may talk about God's love and other virtuous things, but it often merely camouflages their evil intentions. These troublemakers are not peaceable, righteous people, but, like their spiritual father, Satan, they are of the lie (see John 8:44; II Thessalonians 2:9-12), and oppose those who truly serve Him.
2. Why do demons invade people? Mark 1:23; Luke 4:33.
Comment: The demon invaded the man's mind, overriding his conscious personality, which allowed the unclean spirit to speak through him (Mark 5:7). Knowing that God's Son would come in the flesh to save humanity, and that God is raising firstfruits for His Family among humanity, the demons resentfully lust for victory over people. Though God mercifully limits demon possession, He often allows demons to influence people heavily, as seen in the unclean spiritual condition of this society. Thus, Christians must beware of worldly relationships (II Corinthians 6:15-18).
3. Does the demon recognize Jesus as the Son of God? Why does He prohibit its testimony? Mark 1:24-25; Luke 4:34-35.
Comment: The great archangel who later became Satan and his legions of angels were once clean spirits until they rebelled against the Most High God. In the ages before human history, they dwelled in the preincarnate Christ's presence, and thus they are very aware of His attributes. Thus, the demon in the synagogue does not hesitate to acknowledge "the Holy One of God."
Jesus does not let it speak of Him because He would not receive testimony from such a lying, diabolical source. For the same reason, Paul refuses the public witness of a fortune-telling spirit in Philippi (Acts 16:16-18). There can be no association between Christ and Satan. Jesus does not even carry on conversations with demons, but He commands and instructs them by the power and authority of His heavenly Father (Matthew 8:31-32; Mark 1:34).
4. How does Jesus expel the unclean spirit? Mark 1:25-28; Luke 4:35-37.
Comment: Jesus commands the demon to leave, giving it a short, direct order backed by God's authority. He does not rebuke the man, because the unclean spirit had possessed him, yet each of us must resist the influence of demons (I Peter 5:8-9). Jesus tells the demon, "Hold your peace," which actually means "be gagged or muzzled," a phrase He also uses to calm the storm in Mark 4:39. The unclean spirit does not speak again, but obeys in rage and anguish.
By his own power or authority, no man can cast out demons. Even the archangel Michael, not daring to revile Satan, called on the power and authority of God to rebuke him (Jude 9), setting a right example for us. Similarly, in rebuking the "spirit of divination" at Philippi, Paul says, "I command you in the name of Jesus Christ to come out of her" (Acts 16:18).
Because of Christ's authority in performing this miracle, the people in the synagogue are "amazed," a word meaning "to stupefy" and "to dumbfound or flabbergast." They express their astonishment in questions: "What is this? What new doctrine is this?" (Mark 1:27), as well as by immediately rushing away to tell everyone they can. The word translated "amazed" also can mean "to terrify" and "to be frightened." The people are not only astounded but also fearful of God's power through Jesus.
The focus of the testimony is on how Jesus exorcises the demon: simply by His command, which shows the power of God's Word. Contemporary Jewish doctrine for casting out demons was much different, as exorcists among them sometimes appeared to cast out demons by prayers or chants. Christ, however, does not cajole or request demons to leave, but authoritatively commands them to come out. The world has its weak and useless methods to appease evil and entice it to surrender, but Christ commands its defeat.