As an aside, I compare demonic possession to being abducted by what are called aliens and who are, in my opinion, demons from another dimension. There's a theory, one I believe, that Christians can only be abducted if they give consent.
I took a survey in two Bible studies that I attend asking the straight forward question, “Do you think a Christian can be demon possessed? A simple yes or no question about being possessed. Nevertheless, two men stated that there is a difference between being obsessed and possessed. Yes, of course, there is a difference; to be obsessed is to be preoccupied and to be possessed is to be controlled. For a minute I thought we were going to get into a discussion of how many angels can dance on head of a pin. Finally, there was 100% agreement that Christian cannot be possessed unless they invite demons into their life.
A Ouija board can be a gateway by which a demon will possess a person. The late Jane Roberts was using a Ouija board when an entity jumped on it named Seth. Ms. Roberts wrote many best-selling books purchased by many. She wrote entertaining fiction, however, I found that the books she channeled from Seth to be unintelligible.
Mary Magdalene met Jesus, Mark 16:9, “Now when Jesus was risen early the first day of the week, he appeared first to Mary Magdalene, out of whom he had cast seven devils (G1140).” After that Mary Magdalene became a follower of Jesus and never again was there any mention of her having demons.
James 2:19, “Thou believest that there is one God; thou doest well: the devils (G1140) also believe, and tremble”
G1140, a demon or super natural spirit (of a bad nature): - devil.; a daemonic being; by extension a deity: - devil, god.
As an aside, even demons believe in the existence of God and fear their eventual punishment/ destination. Matthew 8:29, “And, behold, they cried out, saying, What have we to do with thee, Jesus, thou Son of God? art thou come hither to torment us before the time?” The demons asked, “If thou cast us out, suffer us to go away into the herd of swine.” The demons entered the swine they “ran violently down a steep place into the sea and perished in the waters.” The swine could not be possessed without permission from Jesus. Just as demons cannot possess Christians unless invited in.
Mark 3:28-29, “28 Verily I say unto you, All sins shall be forgiven unto the sons of men, and blasphemies wherewith soever they shall blaspheme: 29 But he that shall blaspheme against the Holy Ghost hath never forgiveness, but is in danger of eternal damnation:”
Here Temple leaders committed the unpardonable sin by accusing Jesus of casting out demons by demonic power when it was through the power of the Holy Spirit. They not only rejected Jesus, they referred to the Holy Spirit as a demon. Little sins and not so little sins and all kinds of sins can be forgiven but not the sin of blasphemy against the Holy Spirit, this is an eternal sin.
Christians do not become possessed by demons unless they first invite them in. Ouija boards are one of the tools used by demonic forces to enter someone's life. The best cure is prevention. Do not allow the occult into your homes thereby exposing your unbelieving family members to demonic entities.