Demon possession
The Bible gives some examples of people possessed or influenced by demons. From these examples we can find some symptoms of demonic influence and gain insight as to how a demon possesses someone. Here are some of the biblical passages: Matthew 9:32-33; 12:22; 17:18; Mark 5:1-20; 7:26-30; Luke 4:33-36; Luke 22:3; Acts 16:16-18. In some of these passages, the demon possession causes physical ailments such as inability to speak, epileptic symptoms, blindness, etc. In other cases, it causes the individual to do evil, Judas being the main example. In Acts 16:16-18, the spirit apparently gives a slave girl some ability to know things beyond her own learning. The demon-possessed man of the Gadarenes, who was possessed by a multitude of demons (Legion), had superhuman strength and lived naked among the tombstones. King Saul, after rebelling against the Lord, was troubled by an evil spirit (1 Samuel 16:14-15; 18:10-11; 19:9-10) with the apparent effect of a depressed mood and an increased desire to kill David.