Mental illness & demonic oppression (Part 3)
2/6/2026
Building off of the first and second posts in this series, now we turn to look at someone who was affected by demons and behaved erratically. Mark reads,
"When Jesus got out of the boat, a man with an impure spirit came from the tombs to meet him" (5:2).
So how was the Gerasene man (Luke tells us there were at least two men) affected by demonic oppression?
This story deserves a closer look. Mark gives us a good description of his condition:
He experienced possible sleeplessness and a decreased need for sleep. “Night and day among the tombs and in the hills he would cry out” (Mk.5:5).”
This man had (at times) increased strength. "...he had often been chained hand and foot, but he tore the chains apart and broke the irons on his feet" (Mk. 5:4).
He also exhibited bizarre behavior (Lk.8:27). “For a long time, this man had not worn clothes” (Lk.8:27). And also, “(He) cut (lit. to gash, cut up in pieces) himself with stones” (Mk.5:5). There is good reason to believe this cutting was at least a way to cope with his pain, but may have been attempts to take his own life.
These behaviors are symptoms of mental illness, but let’s be clear—they identify a severe mental state. Mark describes his behavior as deviant, distressing, dysfunctional, and dangerous—the “four Ds” of psychological abnormality. This man clearly lost touch with reality, as evidenced by his nakedness, yelling, and violent behavior. In psychological terms, he would have experienced psychosis.
The National Alliance on Mental Illness (NAMI) describes psychosis:
"Most people think of psychosis as a break with reality. In a way it is. Psychosis is characterized as disruptions to a person’s thoughts and perceptions that make it difficult for them to recognize what is real and what isn’t. These disruptions are often experienced as seeing, hearing, and believing things that aren’t real or having strange, persistent thoughts, behaviors and emotions. While everyone’s experience is different, most people say psychosis is frightening and confusing."
Early signs of psychosis are: trouble thinking clearly, paranoia, a decline in personal hygiene, strong and inappropriate emotions, persistent and unusual thoughts, and withdrawing from family or friends. We can observe all of these in the man of the Gerasenes. But that doesn't exactly answer the question:
Was there a connection between his mental condition and his demonic oppression?
The text doesn’t tell us whether demons caused his mental distress, or followed it. In other words, was he mentally ill because of demonic oppression? Or was he mentally ill and then became oppressed by demons? Did one come before the other, or did they both happen in conjunction?
What we do know is that this man was experiencing symptoms of severe mental illness while he was also being oppressed an excessive number of demons.
Keep in mind that this isn’t the norm.
The next highest number of demons we’re told about is Mary Magdalene, “from whom seven demons had come out” (Lk.8:2). Here Mark describes a legion. “’My name is Legion,’ he replied, ‘for we are many’” (Mk.5:9, 15). The Greek word λεγιὼν is used in ancient literature to describe a company of soldiers. During Augustus’ reign, a legion of soldiers was 6826 men—6100-foot soldiers and 726 horsemen. Jesus used the same word when he said, “Do you think I cannot call on my Father, and he will at once put at my disposal more than twelve legions of angels [that would be more than 81,000 angels!]” (Matt.26:53)? The point in the Gerasene man's case is that this indicates an excessive number of demons, which tells us that the man of the Gerasenes is an extreme case. We've never seen this level of demonic oppression in the Bible.
Furthermore, we don’t usually see this type of psychotic behavior in people with mental illness either. Such severe behavior represents only 2-3 percent of all mental illness. About 97 percent of persons suffering with mental illness never experience these symptoms, which actually seems to be reflected in Scripture, since only one man is described in this way.
We must be extremely careful here. Just because this man suffered from symptoms associated with mental illness, doesn’t mean that every person suffering with mental illness is demon oppressed. Nor does it mean that everyone or even most people suffering with mental illness experience the same symptoms. Scripture only makes the connection once, and even then it describes a very extreme case. Instead of assuming this is normative, we should take it at face value. What we can conclude is that he suffered from extreme demonic oppression and he entered a state of psychosis. The two are related somehow, but we can’t say exactly how.
Having considered what Scripture teaches regarding both mental illness and demonic influence, we will draw some conclusions in the last post in this series.