Demons in the New Testament

In the New Testament, demons are seen as the helpers of Satan, who cause sickness and disaster.

From the Hellenistic period certain movements of Judaism started seeing demons as evil spirits that were subordinates of Satan. Under Satan’s instructions they brought disaster to people. God and his angels stood in opposition to Satan and his demons and eventually the demons would be defeated for ever by God in a final battle between God and Satan. This image can be found in the New Testament as well.

In the Synoptic Gospels a wide variety of afflictions such as aggression (Matthew 8:28), epilepsy (Luke 9:39), blindness (Matthew 12:22) and deafness (Mark 9:25) were attributed to demons. However, not all illnesses were explained in this way, and some afflictions were seen as an illness on one occasion, but on another as possession.
Driving out demons was an important part of Jesus’ work on earth. His power over demons is proof of the new Kingdom that starts with him (see for example Matthew 12:25-29). By subjugating the demons, Jesus shows that he is more powerful than Satan and that he will eventually defeat him. Jesus passed on his power over demons to his disciples (see for example Mark 3:13-19). Other believers were also able to cast out demons (see for instance Acts 8:5-8).

In other places in the New Testament, the emphasis is more on demons as moral and spiritual adversaries of the saints. Demons try to lure the believer away from his faith and tempt him to sin (1 Timothy 4:1).