This difficult and sensitive question requires careful consideration. In the New Testament, Jesus often cast out a demon from people who had physical diseases, as well as some people whose descriptions appear similar to modern psychological disorders. How can we distinguish between psychological disorders and demon possession?
How can we tell the difference between a psychological disorder and demon possession?
A look at biblical examples indicates that these categories can overlap or exist at the same time in the same person. For example, the demon-possessed man of Gadarenes was known for cutting himself, not wearing clothing, and living in a cemetery (Mark 5:1-20). Jesus cast out the demons from him and the man's mental health returned to normal. In this case, a person with mental health issues and demonic possession was cured of both at the same time.
In the case of King Saul, he often was "troubled by an evil spirit" and sought music from David's harp to bring him relief. This ancient form of music therapy helped with his mental health situation, but did not change his spiritual life. In the end, Saul's heart turned away from God and led to negative consequences.
How should we deal with similar situations today? The clearest way is to have a person evaluated for mental health disorders. If something physical or mental is detected, then these issues should be treated appropriately. There is no reason to deny medical or mental health treatment to someone because of perceived demonic influences.
In addition, regardless of whether a person's disorder is psychological, spiritual, or a combination of both, we can pray for the person's life in all areas. This includes prayer for salvation, prayer for improved health, and prayers against any spiritual forces of evil that may be present.
Another factor to consider is the spiritual beliefs of the person. The Bible indicates a person who is truly a Christian cannot be possessed by a demon (2 Corinthians 1:22). If a person is a Christian, then he or she is not possessed, but may have other concerns that need to be addressed. These could include spiritual factors and/or possibly medical or mental health issues.
Though a Christian cannot be possessed by a demon, one could influence him or her. For example, even the apostle Peter's thoughts were sometimes wrongly influenced. Jesus once told him, "Get behind me, Satan! You are a hindrance to me. For you are not setting your mind on the things of God, but on the things of man" (Matthew 16:23). Peter also denied knowing Jesus three times in one night, yet was restored to ministry and was a top leader in the church.
It is clear God wants us to pray for those in trouble, regardless of what kind. We are also called to responsibly diagnose and treat psychological concerns whenever possible. Through both practical actions and spiritual prayer and concern, we can better help those who struggle with mental or spiritual problems.
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