Demonology – A Study Outline


A.    Extra-biblical Sources

1.     In religion, folklore, and mythology a demon is a supernatural being that has generally been described as a malevolent spirit.
2.     Iranian and Indo-European traditions accept the notion that demons [Daewan] have existed for millennia.
3.     Ancient Egyptians also believed in demonic monsters that might devour living souls while they traveled towards the afterlife, although demons per se did not exist in Ancient Egyptian belief.
4.     The Greek conception of a demon (daímōn) appears in the works of Plato and many other ancient authors, but without the evil connotations.
5.     Jewish folklore speaks of Lilith, a female demon, who originally was Adam’s first wife. She is said to come and kill male infants in the night unless the names of three angels are on an amulet by the infant’s side.

B.    Biblical References

1.     The Old Testament
a)    Perhaps the “Sons of God” and Nephilim are references to demons (Gen 6:2, 4).
b)    There was worship of Goat Demons or Satyrs in the land (Sairim – Lev 17:7).
c)     The worship of idols was equivalent to demon worship (Shedim – Deut 32:17 cp. 2Ch 11:15. Note: Idol worship is a form of demon worship as demon spirits impersonate the idol and work their wicked strategies through the system of false religion tied to the false god. MSB)
d)    Pagans and Israelites sacrificed the children to demons (Psa 106:37; Deu 12:31, 2Ki 17:17).
e)     Saul was terrorized by an evil spirit (i.e. demon) (1Sa 16:14).

2.     Christ’s Testimony
a)    Christ spoke of demons (Mat 12:28; 25:41; Luk 10:20; Joh 8:49)
b)    Christ cast out demons (Mat 10:8; Mar 1:39; Luk 4:35)
c)     Christ spoke of demons (Mat 12:28; 25:41; Luk 10:20; Joh 8:49)
d)    Demons spoke to Christ (Mar 5:7, 9, 12; Luk 4:41)
e)     Christ’s disciples cast out demons (Mar 6:13)

3.     The New Testament
a)    Many demons and evil spirits were cast out in Acts (Act 5:16; 8:7; 19:12).
b)    Paul stated to the Corinthians that idol worship was the same as demon worship (1Co 10:20-21).
c)     Paul reveals that demons are responsible for promoting false doctrine (1Ti 4:1).
d)    James teaches that demons shudder at the name of God (Jam 2:19).
e)     Satan’s judgment is depicted in Revelation (Rev 12:9).


A.    Origin

1.     At one time demons were unfallen angels who sinned and consequently fell (2Pe 2:4).
2.     The unfallen angels sinned when one third of the total number left heaven and followed Satan (Rev 12:4).
3.     Demons follow their leader Satan (Mat 12:24-26).

B.    Characteristics

1.     Demons, because they are angelic beings, though fallen, are spirit beings (Eph 6:12).
2.     Demons are frequently called “evil spirits” (pneumátōn ponêrṓn Luk 7:21; Act 19:12; Satan is called the “Evil one: – ho ponêrós; Mat 17:18 cp. Mar 9:25).
3.     Generally, they are invisible, but can be audible (Acts 19:15; Rev 9:1-12).
4.     Demons are personal beings that have intellect (Jam 2:9; Mat 8:29), emotion (Luk 8:28), and will (Luk 8:32).

C.    Autonomy

1.     It is clear that most demons are autonomous in that they are active in the world today (Eph 6:12).
2.     However, there are demons that are confined.
a)    Some are and will be temporarily confined. The “Abyss” is the place of temporary detention for wicked angels. If not all, then many will be loosed in the End Times (Luk 8:31;
b)    Others are permanently confined until judgment. Tartarus is probably not the same as the Abyss and is the place of permanent confinement for wicked angels until judgment (Jude 6; 2Pe 2:4). It is akin to the Tartarus of Geek Mythology and contributes support for demons activity in Gen 6.

D.    Destiny

1.     The demise of Satan and all the fallen angels will be the lake of fire.
2.     This is their final and eternal place of punishment (Mat 25:41; Rev 20:10).


A.    Sons of God in Gen 6:1-6

1.     One of the most controversial texts in Scripture is Gen 6:1-6. The controversy revolves around whether or not demons had something to do with co-mingling with the daughters of men.
2.     The three views concerning the interpretation of the “sons of God” are:
a)    View #1 – Sons of Seth
b)    View #2 – Human Kings
c)     View #3 – Demons

View #1 – Sons of Seth

a)    This view suggests that the sons of Seth married from the evil Cainites.
b)    This view sees the sons of Seth as the godly line. If that were the case, then why did they married the ungodly Cainites? Also, if the Sethites were godly, why did God need to destroy the earth? Why did such a union produce giants?

View #2 – Human Kings

a)    This view suggests that Human Kings became despots and took women from anywhere to be their harem.
b)    It is very difficult to understand why these evil kings would be called, “sons of God.” Why did such a union produce giants?

View #3 – Demons

a)    The language used in the context strongly suggests demonic activity. This view seems to agree with the context more than the other views. There also appears to be support from other passages of Scripture.
b)    The detailed arguments are:

(1)   The term in the OT, “sons of God,” is almost always identified as angelic beings whether fallen or unfallen (Job 1:6; 2:1; 38:7 cp. Psa 29:1; Psa 89:6).

Note: The Nephilim were not the offspring of the demonic union but already on the earth (“and also afterward…when the sons of God…”). The word Nephilimcomes from the root naphalwhich means “to fall.” In this case, it could be, “those who cause to fall.” They would have been oppressors, conquerors, and warriors who also contributed to the wickedness on the earth.

(2)   If the demons cohabited with human woman, there would appear to be some accountability on the willingness of the human women. The Book of Enoch alludes to the idea that these women were taught witchcraft, occultic practices, and magic. Such demonic activities would have influenced their offspring as well as society. Contextually, this would have been a major contributing factor to the wickedness in the world and a reason for God to destroy it (Gen 6:5).

Note: Jesus’ statement concerning angels not marrying or given in marriage (Mat 22:30; Mar 12:25; Luk 20:35) does not rule out the possibility of demons possessing the bodies of individuals in order to cohabitate with human women.

(3)   Peter warns of God’s wrath against sin and apparently gives chronological examples.

(a)   2 Pet 2:5: the example is given of Noah’s flood which is found in Gen 6:8.
(b)   2 Pet 2:6: the example is given of Sodom and Gomorrah found in Gen 19:12-28.
(c)   But prior in 2 Pet 2:4: If we stick to a chronological perspective, when did the angels sin? The only possible biblical account would be Gen 6:2-4. (We do not read of a biblical account of Satan’s fall until Isa 14/:12-14. Furthermore, Satan and many of his angels are not confined).

(4)   In addition, Peter speaks of a punishment so severe for those particular angels that they would be held in prison until judgment. We know that other demons, which were placed in prison, were only temporarily confined (Rev 9:1-11). Jude 6 appears to confirm that there are demons who are permanently confined until judgment. What did those particular angels do that was so horrendous? Jude explains, [they were] angels who did not keep their own domain, but abandoned their proper abode. (The proper abode cannot merely mean that they left heaven, otherwise, Satan and his angels would be permanently confined.) It very likely suggests that the cohabitation of angels and human woman produced a hideous and unnatural union which violated the God-ordained order of human marriage and procreation (Gen. 2:24).

(a)   The Abyss seems to refer to a temporary confinement (Luk 8:31; Rev 17:8; Rev 20:1-3).
(b)   While Tartarus seems to refer to a permanent confinement until God’s judgment in the lake of fire (Rev 20:10).

(i)    In 2Pe 2:4, the Greek word for “hell” is not geenna but the verbal form of Tartaros.
  (ii)   Tartaros was regarded by the Greeks as a place of permanent torment and punishment below Hades. It is also mentioned in the pseudepigraphal book of Enoch as the place where fallen angels are confined. This does not mean that Peter believed in Greek mythology, but perhaps his word choice of tartarus points to a belief of demonic cohabitation in Gen 6:2-4.

(5)   Antiquity lends its support to the demon view. Such writings are not inspired and they may even be spurious. However, they can give an understanding of the general belief of that era. Even Jude quotes a small portion of Enoch.

(a)   The Book of Enoch (200 B.C.) espoused the view of a co-mingling between angelic beings and human women. And it came to pass when the children of men had multiplied that in those days were born unto 2 them beautiful and comely daughters. And the angels, the children of the heaven, saw and lusted after them, and said to one another: ‘Come, let us choose us wives from among the children of men 3 and beget us children. (Enoch 6:1-3).
(b)   Josephus recorded the contemporary view that in Gen 6, angelic beings took wives…For many angels of God accompanied with women, and begat sons that proved unjust (The Works of Josephus, Bk. 1, Ch.3:73).
(c)   It was supported by some of the earliest Christian writers, Justin, Irenaeus, Clement of Alexandria, Tertullian, and Origen. It is also supported by many modern commentaries.

B.    Demon Possession

1.     The Definition of Demon Possession
a)    Demon possession is a condition in which one or more demons inhabit the body of a human being with the purpose of controlling it. (John MacArthur,Jesus’ Power over the Supernatural)
  b)    The indwelling and controlling or at least temporary domination of an individual’s personality and body. (Gibson, Lancaster Bible College)
  c)     The inhabiting of a human by one or more demons who exercise various degrees of control with resultant physical, psychological, and spiritual manifestations (C. Fred Dickason, Angels: Elect & Evil, Chapter 20, Moody Press, 1995 Edition, p.198).
d)    Charles Ryrie defines demon possession as A demon residing in a person, exerting direct control and influence over that person, with certain derangement of mind and/or body. Demon possession is to be distinguished from demon influence or demon activity in relation to a person. The work of the demon in the latter is from the outside; in demon possession it is from within. By this definition a Christian cannot be possessed by a demon since he is indwelt by the Holy Spirit. However, a believer can be the target of demonic activity to such an extent that he may give the appearance of demon possession. (Charles C. Ryrie, Study-Graph: Bible Doctrine II)

2.     The Biblical Terminology of Demon Possession
a)    “Demon Possessed or Demoniacs” (NASB)
(1)   This word comes from the Greek word daimonízomai, which means to be inhabited, possessed, and controlled by a demon.
(2)   It is found 13 times in the N.T. (Mat 4:24; 8:16, 28, 33; 9:32; 12:22; 15:22; Mar 1:32; 5:15, 16, 18; Luk 8:36; Joh 10:21)
(3)   It is always in the passive voice and is usually a present participle. So it would be translated, “being possessed and controlled by a demon.”
(4)   Mar 5:18 and Luk 8:36 are aorist passive participles referring that the demon no longer inhabits and possesses the individual.
(5)   Every instance of this word refers to being inhabited by a demon.
b)    “Has a Demon or Unclean Spirit”
(1)   The phrase “has a demon” (daimónion échei) implies that there is a demon dwelling within an individual (Mat 11:18; Luk 4:33; 7:33; Joh 7:20; 8:48, 49, 52; 10:20).
(2)   In Mar 3:30, the phrase is used with an “unclean spirit” but carries the same idea of possession or habitation.
c)     “Troubled With Unclean Spirits”
(1)   Two Scriptures are given with the expression of being “troubled” (enochléō) or “afflicted (ochléō) with unclean spirits.
(2)   The word ochléō means to disturb or torment and very well could explain what happens to a person when possessed (cp. Mar 5:5).
(3)   In Luk 6:18 and Act 5:16, individuals were being healed (therapeúō – heal or cure; Eng. therapeutic) from demonic troubling, quite possibly by casting out the demons that inhabited them. The same word (therapeúō – heal or cure; Eng. therapeutic) is used when Jesus cast out demons of those possessed by demons. (Mt 12:22; 17:18; Luk 7:21; 8:2)

3.     The Characteristics of Demon Possession
a)    In the Middle Ages, a period of superstition and ignorance, a list of symptoms were established to confirm demonic possession.
  (1)   The ability to curse/blaspheme in languages unknown to the person. 
  (2)   The ability to find secret things, read the mind, and divine future happenings. 
  (3)   The ability to make physical efforts abnormal for that person. 
  (4)   The act of spitting or vomiting every object the demons would have made the person swallow. 
  (5)   Fear and/or hatred of holy objects. 
  (6)   The inability to say the word “Christ.” (Wikipedia, Demonic Possession)
(7)   Other characteristics noted by people at that time:
(a)   …that oppressed persons had an ugly and terrible aspect, wrathful eyes, bluish lips, foam coming off their mouth; their body was almost permanently shaking, when they spoke their tongue came abnormally out, their speech consisted mainly in curses and blasphemies, and they were able to imitate animal sounds as well as to speak with human-like voices with a strange sound and a different pitch of theirs. However, these symptoms as described are not always in accordance with scripture (ibid).
b)    Listed below are the various expressions of demon possession in Scripture. We should not jump to the conclusion that isolated symptoms equate to demon possession. Characteristics of Demon Possession in Scripture are:
(1)   Convulsions (Mar 1:26; 5:4; 9:20-26; Luk 4:35; 9:42)
(2)   Falling (Mat 17:15)
(3)   Stretched and disjointed body movements (Mar 9:18)
(4)   Deformity (Luk 13:11)
(5)   Foaming at the mouth (Mar 9:18, 20; Luk 9:39)
(6)   Shrieking and screaming (Mar 1:26; 5:5; 9:26; Act 8:7)
(7)   Demons speaking (Mar 1:34; 3:11; 8:31; Luk 4:41; 8:28; Act 16:17; 19:15)
(8)   Deaf (Mar 9:25-26; Luk 11:14)
(9)   Mute (Mar 9:25, 32-33; Luk 11:14)
(10) Blindness (Mat 12:22)
(11) Super-human strength (Mar 5:4; Luk 8:29; Act 19:16)
(12) Self-destruction (Mar 5:4, 5; Luk 9:39)
(13) Violence (Mat 8:28; Mar 5:4; Act 19:16)
(14) Isolation (Luk 8:29)
(15) Lunacy (Mat 17:15; Mar 5:15; Luk 8:35; Joh 10:20)
(16) Nakedness (Mar 5:15; Luk 8:27; Act 19:16)
(17) Divination (Act 16:16)
(18) Leave and return (Mat 12:45)
(19) Reluctance to leave (Mat 17:16)
(20) Multiple demons (Mat 12:45; Mar 5:15; Luk 8:30)

4.     The Extent of Demon Possession
a)    Can a Christian be demon-possessed?
(1)   Perhaps one of the most hotly debated topics centers around the question, “Can a Christian be demon-possessed?”
(2)   Merrill F. Unger unequivocally wrote in 1952 in his classic book, “Biblical Demonology,”

The very nature of the believer’s salvation, as embracing the regenerating, sealing, indwelling, and filling ministry of the Holy Spirit, placing him “in Christ,” eternally and unforfeitably, is sufficient explanation why he is not liable to demon inhabitation. (pg. 100).

(3)   Yet in 1977, three years before his death, Dr. Unger wrote,

Who dares assert that a demon spirit will not invade the life of a believer in which the Holy Spirit has been grieved by serious and persistent sin and quenched by flagrant disobedience? . . . A demon . . . enters as a squatter and an intruder, and is subject to momentary eviction. . . . Only as the believer fails to walk by faith does he fall into sin, which if it is not confessed and curbed, may ultimately result in the forfeiture of the Spirit’s power to shield him from demonic invasion. (Merrill Unger, What Demons Can Do to Saints [Chicago: Moody, 1977], pp. 51–52).

(4)   There was obviously a change in Dr. Unger’s position. Why? It apparently was the fallacious appeal to subjectivism (experience) and authority (influence) by Dr. V. Raymond Edman, chancellor of Wheaton College, which Unger alluded to,

For many years the late chancellor of Wheaton College, Dr. V. Raymond Edman, taught that a Christian under certain circumstances could be invaded by demon powers. His first-hand experience with crude demonism, as a result of missionary labors in Ecuador in his earlier years, gave Dr. Edman an understanding of the subject of demonism not possessed by purely theoretical Bible interpreters.

In 1955, three years after the appearance of Biblical Demonology, Dr. Edmanwrote me a letter in which he stated his convictions on the subject. At the time, I espoused the purely theoretical position which did not square with the authenticated facts of experience. (ibid. pg. 61).

(5)   In addition, Dr. Unger was influenced by various teachers, who taught that believers could be demon-possessed, like Hobart Freeman, Kurt Koch, C.S. Lovett, J.A. McMillen, T.J. McCrossan, J. L. Nevius, J. Penn-Lewis, A.B. Simpson, and Charles Ussher.
(6)   There are prolific writers today who espouse the demons possessing believers such as, C. Fred Dickason, Chairman of Theology at Moody Bible Institute, who in his book, Angels Elect and Evil, writes,

A genuine Christian may become possessed at least to some degree, even to the point where they speak with strange voices or in foreign languages. (pg. 191).

(7)   However, we must not rely on experience, subjective theologians, or stories but must rely solely on the Scriptures to dictate our beliefs.
b)    Biblical Arguments Against Believers Possessed by Demons
(1)   First, there are no clear examples in the Scriptures where a genuine believer was inhabited or invaded by a demon. Neither is there any warning to believers for the possibility of being possessed by a demon.
(2)   Secondly, 2Co 6:15-16 emphatically states that Christ and Belial (ancient name for Satan) have no harmony (sumphṓnêsis – agreement or concord) or commonality (merís- part or portion) together.
(a)   The clear implication is that Christ and Belial would not share habitation over a believer (15).
(b)   Both the Holy Spirit and a demon could not reside in a believer at the same time. In addition, it is the Holy Spirit who permanently resides in the believer (Eph 4:30 – note: even if a believer grieves the Holy Spirit there is permanent residence).
(c)   God would never have an agreement (sugkatathesis – put something down together) with idols (16). By implication neither would He have an agreement with demons (who are behind the idols, 1Co 10:19-20) in the temple of the believer’s body.
(3)   Another argument is the marvelous deliverance that the believer already possesses in Christ (Col 1:13).
(a)   The believer was rescued “from” (lit. ek – out of) the “domain” (exousia – authority) of darkness.
(b)   Furthermore the believer was transferred (methistemi – remove from one place to another) to (lit. eis – into) the kingdom of the Son.
(c)   Being delivered out of the authority of Satan, how could a believer be possessed or inhabited by a demon?
(d)   Being placed into the kingdom of the Son, how could that kingdom ransacked by a demon in order to invade and inhabit a believer?
(4)   Still, another argument is that the believer has overcome the evil one (1Jo 2:13). It would be difficult to imagine that the believer, who has overcome the evil one, could also be overcome and inhabited by a demon.
(5)   The Holy Spirit is greater than he (Satan and his demons) that is in the world (1Jo 4:4).
(a)   God the Holy Spirit, who permanently indwells the believer, is omnipotent and greater than Satan and his demons.
(b)   Nowhere in Scripture do we read that the Holy Spirit would ever relinquish his power or position to demons under any circumstance.
(6)   Finally, salvation includes the believer’s deliverance and protection from Satan (1Pe 1:5; 1Jo 5:18), which is not the case with the world (1Jo 5:19). Therefore, believers are taught to resist the devil (Jam 4:7) but never cast them out of each other.
c)     Arguments For Believers Possessed by Demons
(1)   First of all, the proponents of demons possessing believers argue that they do not believe in demon “possession.” The word “possession” is very troubling for these proponents because they claim the word carries with it the connotation of ownership. They assert believers can only be owned by Christ not demons.
(a)   They would argue then that a believer cannot be possessed, but may be “demonized.”
(b)   Make no mistake, they still believe that a “demonized” believer can be inhabited by a demon; they just prefer to refrain from saying, “possessed.
(c)   However, this does very little for the debate because what used to be meant by the term, “possessed” has merely been replaced by the term, “demonized”or “inhabited.” It is the same old debate just with different words.
(2)   The only argument that should matter to any believer is the argument from Scripture. It is at this point, by their own admission that the proponents of demons possessing believers digress.
(a)   If there is credit due, it is due to those statements, which admit that they have no clear evidence from Scripture.

Thus we cannot conclusively say that the Bible clearly presents evidence that believers may be demonized. (Dickason, Demon Possession and the Christian: A New Perspective, Ch. 7)

(b)   If the threat of the demon possession to believers is as grave as these proponents make it out to be, or if the demon possession of believers was going on in the early church, would you not think that some instruction would have been given on casting demons out of believers in the New Testament?
(c)   Therefore, the proponents of demons possessing believers must seek elsewhere for evidence such as experience and clinical studies.

Thus we are left to look for other types of evidence that may contribute to answering our question: Can genuine believers be demonized? (ibid.)

I have encountered, from 1974 to 1987, at least 400 cases of those who were genuine Christians who were also demonized. . . I would not claim infallible judgment, but I know the marks of a Christian and the marks of a demonized person. I might have been wrong in a case or so, but I cannot conceive that I would be wrong in more than 400 cases. The burden of proof lies with those who deny that Christians can be demonized. We must deduce that those who deny that Christians can be demonized generally are those who have not had counseling experience with the demonized. Their stance is largely theoretical. (ibid. pg. 175)

These case studies taken from my personal written and taped records demonstrate that genuine believers can and indeed were inhabited by demons. (ibid. pg. 213)

Clinical evidence abounds that a Christian can be demon-controlled as a carry-over from pre-conversion days or can fall under Satan’s power after conversion and become progressively demonized, even seriously.(Merrill F. Unger, What Demons Can Do to Saints, rev. ed. pg. 150.)

(3)   One argument from Scripture used to support that a believer can be inhabited by a demon involves the woman who was bent double (Luk 13:11). She was not only delivered from a sickness “caused by a spirit” (11), but was called a “daughter of Abraham” (16).
(a)   The assumption is the phrase, “daughter of Abraham,” makes her a believer. However, the phrase only indicates that she is from the race of Abraham, i.e. a Jew, the same as Zaccheus (Luk 19:9).
(b)   Even the fact that she went to a synagogue and also glorified God for her healing does not mean the same as trusting in Christ as Savior.
(c)   Some even question whether this is a legitimate case of demon possession.
(d)   This is a weak argument at best.
(4)   Another argument cited from Scripture to support that a believer can be inhabited by a demon is the troubling of King Saul (1 Sam. 18:10-11; 19:9-10). On two occasions, King Saul had an evil spirit upon him.
(a)   However, being the anointed King of Israel did not automatically make Saul a believer.
(b)   Furthermore, his actions were certainly suspect as to whether he was a genuine believer or not.
(c)   Even if one were to argue that Saul was a believer and possessed, it would not be the same comparison because the Holy Spirit did not reside permanently in a believer as He does today.
(5)   Finally, proponents of demons possessing believers say that passages which support the believer’s position in Christ are only understood as a legal standing. Our position in Christ does not prevent the believer from being demon inhabited.
(a)   While these proponents are correct that our position is a legal standing, our position does have some ramifications for our condition but our condition cannot affect our position in Christ.
(b)   In other words, in our position in Christ we have been forgiven of all sin. We do sin, but we are still completely forgiven and we do not lose our salvation.
(c)   In the same way, in our position in Christ we have been delivered from the domain of darkness and placed into the Kingdom of the Son (Col 1:13). While no one is suggesting that believers cannot be oppressed by demons, it would be unbiblical to suggest that our sin or disobedience could return us to the authority and domain of darkness. Making the claim that a genuine believer could be inhabited by a demon, would suggest that we had been returned to the authority and domain of darkness.
d)    Alternative Explanations For Believers Possessed by Demons
(1)   How then do we respond to the many dramatic experiences reported by proponents of demons possessing believers?
(2)   The following are some plausible alternative explanations from an article from the Christian Research Journal written by Brent Grimsley and Elliot Miller entitled, “Can a Christian Be Demonized?” (Summer 1993, pg. 16).

Psychological Sources. Many of these occurrences could be attributed to psychological sources — not only mental illness (which is no doubt a factor in some cases) but also the power of suggestion. In our longterm research of religious movements and phenomena, time and again we have run into a curious fact: intelligent people can become persuaded of improbable beliefs when striking manifestations issue from their own psyches or the psyches of others, or are experienced as external events. These beliefs range from elaborate conspiracies involving satanic ritual abuse of children, to UFO encounters, to past-life recall, to apparitions of Mary or signs in the heavens produced by Mary. In many of these and other cases a common denominator is a contagious anticipation — often set into motion by the leaders of the event — that such manifestations very well may occur. It can be observed that phenomena will be cited in support of almost any belief, no matter how unbiblical. There is much that we have yet to learn about the dynamics of our own minds, and some of these little-understood factors demonstrate a powerful capacity to lead people into psychological self-deception.

Satanic Deception. … Just as it is possible that demonic as well as psychological factors could be involved in alleged UFO encounters, past-life recall, apparitions of Mary, and so forth, so in the case of Christians being delivered of demons. Of course, this is exactly what the proponents of Christian deliverance argue to be the case. But just as deception would be Satan’s true objective in the sensational phenomena cited above, so might it be with exorcisms of Christians. Clearly, the Devil would like us to believe he has more power over us than he actually does. It seems that demons would be capable of producing certain audible, mental, and bodily phenomena from a position external to the Christian in order to create the illusion that the Christian is, in fact, possessed. If they can convince believers that they have the power to control them, then such believers, though actually in control of their own wills, will grant the powers of darkness a degree of control by default. A Christian who resorts to deliverance sessions to gain spiritual victory rather than standing firm in the promises and provisions of Christ has already been greatly neutralized by the enemy.

Possessed, but Not Regenerate. A third possible explanation is that the individuals truly were demon possessed, but were not truly believers. How does one determine who is and who is not a genuine Christian? Only God knows for sure the identities of His elect and the true state of an individual’s soul (see, e.g., 2 Tim. 2:19; 1 Sam. 16:7; and the parable of the wheat and tares in Matt. 13:24-30, 36-43). … We must conclude that it is impossible to ascertain for certain who is truly demon possessed and who is truly a Christian, since these questions have to do with the interior, unobservable conditions of individuals. It is therefore folly to base one’s view on the apparent condition of Christians being demon possessed when the weight of New Testament theology (regarding the kingdoms of Christ and Satan) leans against that view.

e)     Conclusion
(1)   The burden of proof falls on the proponents of demons possessing believers because the church historically and strongly held that believers cannot be demon possessed. Theologically speaking, the evidence must come from the Scriptures and not anecdotal support. Dr. Unger himself wrote,

It pays to put God’s Word first and human experience second. Experience that is not based solidly on the Word and that does not grow out of an accurate knowledge of the Word is as unstable as a house built on sand. In the storm it will fall, and great will be the fall of it. (New Testament Teaching on Tongues, 1971)

(2)   Once you turn solely to experience and emotion for truth, you open up Pandora’s box to all kinds of error. False teaching uses emotion and experience as way into the church. As Jonathon Edwards wrote,

Spiritual understanding sees what is actually in Scripture; it does not make a new meaning for it. Making a new meaning for Scripture is equivalent to making a new Scripture! It is adding to God’s Word, a practice God condemns (Proverbs 30:6). . . A large part of the false religion in the world is made up of . . . experiences and the false notion they excite. Non-Christian religions are full of them. So (unfortunately) is the history of the Church. These experiences captivate people so Satan transforms himself into an angel of light, deceives multitudes, and corrupts true religion. Church leaders must be constantly on their guard against these delusions (The Experience That Counts! edited by N.R. Needham [London: Grace Publications Trust, 1991], pp. 89–90).

(3)   We conclude that we agree with Dr. Unger’s original biblical proposition,

The very nature of the believer’s salvation, as embracing the regenerating, sealing, indwelling, and filling ministry of the Holy Spirit, placing him “in Christ,” eternally and unforfeitably, is sufficient explanation why he is not liable to demon inhabitation. (Unger, Merrill, Biblical Demonology, pg. 100)