Demon possession is when a fallen angel, a demon, enters and occupies the body of an unbeliever. Demons cannot enter a Christian believer because the Christian's body is the temple of the Holy Spirit. If someone is demon possessed Jesus can easily cast it out like it says in Luke 4:35. Demons can enter a person in many other ways. One of them is Idolatry like it says in 1 Corinthians 10:19-21. Demon Influence is the residence of evil in the soul. It can happen to a unbeliever or a believer. This is a method that Satan uses to trap a believer, by introducing something called the "Doctrine of Evil" inside the soul of the born-again believer. Demon influence in the believer comes in the later stages of negativity, or something called backsliding. The first stage of backsliding is some kind of reaction to life it could be discouragement, disillusion, boredom, self-pity, loneliness, frustration, instability, pride and other sins. Whatever makes this happen, that stage makes someone very vulnerable to the attacks of Satan. The second stage of backsliding is a frantic search for happiness like following trends of a sinful nature. This also increases vulnerability, especially as one move's away from the protection of God. The third stage intensifies the first stage, but still only has the possibility of demon influence. It is at the fourth stage of backsliding, in which the soul is not what it used to be. This is when demon influence comes in. The only way to stop this before it happens is to stick to God when times get rough, and put on the full amour of God like it say sin Ephesians 6:10-12.God will never give you a task that you cannot handle. Trust in him and Satan and demons won't have a chance.
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