Luke, chapters 8 & 9

“And the Twelve were with him, as were certain women who had been cured of wicked spirits and sicknesses: Mary who was called Magdalene, from whom seven demons had come out […].”
~Luke 8:1,2

“As Jesus got out onto land, a demon-possessed man from the city met him. For a considerable time he had not worn clothing, and he was staying, not in a house, but among the tombs.”
~Luke 8:27-36

How does a person succumb to demon possession and why did it seem to be so commonplace in Jesus’ day?
Insight On The Scriptures” defines it as “the captive control and influence of a person by an invisible wicked spirit.”
That influence may manifest itself physically, emotionally or mentally through the victim.
Luke’s account demonstrates that it is possible for a person to be possessed by more than one demon, and it is possible for a demon to possess an animal.
When a person opens a portal into the occult, be it by superstitious practices, trying to communicate with the dead, diabolic entertainment, or through witchcraft, he makes himself vulnerable to demon possession.
In the case of King Saul, a demon began to attack him when he became arrogant and defiant in his service to Jehovah and lost God’s holy spirit. (1 Sam. 15:10,11,22,23; 16:14-16,23; 18:10-12)
When Jesus walked the earth, many Jewish leaders in particular had strayed from true worship and their attitude was heavily influenced by demons. (John 8:44)
Modern Christians do not practice exorcism, which tends to combine rites and chants or a combination of words, as if a person could be liberated from demons through magic.
Rather, they put on “the complete suit of armor” of Christian lifestyle and outright reject evil practices. (Eph. 6:11-18; Jas. 4:7)

1 Samuel, chapters 19-22

Michal took the teraphim statue and placed it on the bed, and she put a net of goat hair at the place of [David’s] head, and she covered it with a garment.
~1 Samuel 19:13

Why did David’s wife, Michal, have a teraphim idol if God had forbidden their use (Exo. 20:4,5)?

The Watchtower gives a possible explanation in that her heart may not have been complete toward Jehovah and it is possible that certain superstitions still influenced Israeli culture.

Perhaps David did not know about the idol, but it is also possible that he let her keep it because she was the king’s daughter (Watchtower 06-01-04, p.29, “Questions from Readers”).
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With that the king said to the guards stationed around him: “Turn and kill the priests of Jehovah, because they have sided with David! They knew that he was a runaway, and they did not inform me!” But the king’s servants did not want to lift their hands to assault the priests of Jehovah.
~1 Samuel 22:17

The guards in this story are a fine example of fearing God instead of man (Matt. 10:28).

When human authorities come in direct conflict with God’s will, the right thing to do is to carry out God’s will (Acts 5:29).

This principle alone would avoid modern cases of genocide.