What Are Demons?                                                                      By Jack Kettler

As in previous studies, we will look at definitions, scriptures, lexical, and commentary evidence and confessional support for the purpose to glorify God in how we live.


Demon: A fallen angel that assists Satan in the opposition of God. Demons are evil (Luke 10:17-18), powerful (Luke 8:29), and under the power of Satan (Matthew 12:24-30). They recognized Christ (Mark 1:23-24) and can possess non-Christians (Matthew 8:29). *

Demons: What does the Bible say about demons?

Demons are fallen angels, as Revelation 12:9 indicates: “The great dragon was hurled down—that ancient serpent called the devil, or Satan, who leads the whole world astray. He was hurled to the earth, and his angels with him.” Satan’s fall from heaven is symbolically described in Isaiah 14:12–15 and Ezekiel 28:12–15. When he fell, Satan took some of the angels with him—one third of them, according to Revelation 12:4. Jude 6 also mentions angels who sinned. So, biblically, demons are fallen angels who, along with Satan, chose to rebel against God. **

From the Scriptures about demons:

 “Yea, they sacrificed their sons and their daughters unto devils (demons).” (Psalm 106:37)

From Strong’s Lexicon on the Hebrew:

To demons לַשֵּֽׁדִים׃ (laš·šê·ḏîm)

Preposition-l, Article | Noun - masculine plural

Strong's Hebrew 7700: 1) demon

 “So the devils (demons) besought him, saying, if thou cast us out, suffer us to go away into the herd of swine.” (Matthew 8:31)

From Strong’s Lexicon on the Greek:

daimón: a demon Original Word: δαίμων, ονος, ὁ

Part of Speech: Noun, Masculine Transliteration: daimón

Phonetic Spelling: (dah'-ee-mown)

Definition: a demon Usage: an evil-spirit, demon.

“Then certain of the vagabond Jews, exorcists, took upon them to call over them which had evil spirits the name of the Lord Jesus, saying, we adjure you by Jesus whom Paul preacheth.” (Acts 19:13)

From Strong’s Lexicon on the Greek:

Evil πονηρὰ (ponēra)

Adjective - Accusative Neuter Plural

Strong's Greek 4190: Evil, bad, wicked, malicious, slothful.

Spirits πνεύματα (pneumata)

Noun - Accusative Neuter Plural

Strong's Greek 4151: Wind, breath, spirit.

“But I say that the things which the Gentiles sacrifice, they sacrifice to devils (demons), and not to God: and I would not that ye should have fellowship with devils (demons).”  (1Corinthians 10:20)

“For we wrestle not against flesh and blood, but against principalities, against powers, against the rulers of the darkness of this world, against spiritual wickedness in high places.” (Ephesians 6:12)

From Matthew Poole's Commentary on Ephesian 6:12 we read:

“We wrestle not, not only, or not principally.

Against flesh and blood, men, consisting of flesh and blood, Matthew 16:17 Galatians 1:16.

But against principalities, against powers; devils, Colossians 2:15: see Ephesians 1:21.

Against the rulers of the darkness of this world; either that rule in the dark air, where God permits them to be for the punishment of men; see Ephesians 2:2: or rather, that rule in the dark places of the earth, the dark minds of men, and have their rule over them by reason of the darkness that is in them; in which respect the devil is called the god of this world, 2 Corinthians 4:4, and the prince of it, John 14:30. So that the dark world here seems to be opposed to children of light, Ephesians 5:8.

Against spiritual wickedness; either wicked spirits, or, emphatically, spiritual wickednesses, for wickedncsses of the highest kind; implying the intenseness of wickedness in those angelical substances, which are so much the more wicked, by how much the more excellent in themselves their natures are.

In high places; or heavenly, taking heaven for the whole expansum, or spreading out of the air, between the earth and the stars, the air being the place from whence the devils assault us, as Ephesians 2:2. Or rather, in for about heavenly places or things, in the same sense as the word rendered heavenly is taken four times before in this Epistle, Ephesians 1:3,20 2:6 3:10; being in none of them taken for the air; and then the sense must be, that we wrestle about heavenly places or things, not with flesh and blood, but with principalities, with powers, &c.

Objection. The Greek preposition will not bear this construction.

Answer. Let Chrysostom and other Greeks answer for that. They understood their language best, and they give this interpretation.” (1)

“Now the Spirit speaketh expressly, that in the latter times some shall depart from the faith, giving heed to seducing spirits, and doctrines of devils (demons).” (1Timothy 4:1)

From The Pulpit Commentary on 1Timothy 4:1:

“Verse 1. - But for now, A.V.; saith for speaketh, A.V.; later for the latter, A.V.; fall away for depart, A.V. The Spirit saith expressly (ῤητῶς), only here in the New Testament, and very rare in classical Greek. But the adjective ῤητός, in the sense of something “laid down,” “definite... expressly mentioned,” is common. It was, doubtless, on account of these prophetic warnings of a falling away from the faith, that the apostle gave the preceding heads of Christian doctrine in such a terse and tangible form, and laid such a solemn charge upon Timothy. (For examples of these prophetic utterances, see Acts 11:28; Acts 13:2; Acts 20:23; Acts 21:11; 1Corinthians 12:8; 1Corinthians 14. '30, 32, etc.) Shall fall away (ἀποστησονται). So St. Paul says (2Thessalonians 2:3) that the day of Christ will not be, “except the falling away (ἡ ἀποστασία) come first” (comp. Hebrews 3:12). The faith, objective (see 1Timothy 3:9 and 16, note). This “falling away” is to take place ἐν ὑστέροις καιροῖς, not, as in the R.V., in “later times,” but as in the A.V., “the latter times.” The adjective ὕστερος is only found here in the New Testament. But in the LXX. (e.g., 1Chronicles 29:29; Jeremiah 1:19; Jeremiah 27:17, LXX.), ὕστερος means “the last”" as opposed to “the first.” And so the adverb ὕστερον always in the New Testament (see Matthew 4:2; Matthew 21:37; Matthew 26:60; or more fully ὕστερον πάντεν, 22:27). Here, therefore, ἐν ὑστεροις καιροῖς is equivalent to ἐν ταῖς ἐσχάταις ἡμέραις (Acts 2:17) and ἐν ἐσχάταις ἡμέραις (2Timothy 3:1; comp. James 5:3; 1 Peter 1:5; 2 Peter 3:3; Jude 1:18). It should be observed that in all these passages there is no article. Giving heed (προσέχοντες); as in ver. 13; in 1Timothy 1:4; Titus 1:14; Acts 8:6, and elsewhere. Seducing spirits (πνεύμασι πλάνοις). Such were the "lying spirits" who deceived (ἠπάτησαν) Ahab to his destruction (2Kings 22:22). Πλάνος, seducing, is not elsewhere found in the New Testament as an adjective (see Matthew 27:63; 2Corinthians 6:8 2John 7, in all which places, however, it is almost an adjective). The idea is "causing to wander," or “go astray.” St. John warns his people against such deceiving spirits (John 4:1-6). He calls them generically πνεύμα τῆς πλάνης, “the spirit of error.” Doctrines of devils; i.e. teachings suggested by devils. So the unbelieving Jews suggested that John the Baptist had a devil (Luke 7:33), and that our Lord himself had a devil (John 7:20; John 8:48, 52; John 10:19).” (2)

“Thou believest that there is one God; thou doest well: the devils (demons) also believe, and tremble.” (James 2:19)

From Vine's Expository Dictionary of New Testament Words:

A-1 Noun Strong's Number: g1142 Greek: daimon

Demon, Demoniac:

“A demon,” signified, among pagan Greeks, an inferior deity, whether good or bad. In the NT, it denotes “an evil spirit.” It is used in Mat 8:31 mistranslated "devils."

Some would derive the word from a root da--, meaning, “to distribute.” More probably it is from a similar root da--, meaning, “to know,” and hence means “a knowing one.”

A-2 Noun Strong's Number: g1140 Greek: daimonion

Demon, Demoniac:

Not a diminutive of daimon, No. 1, but the neuter of the adjective daimonios, pertaining to a demon, is also mistranslated “devil,” “devils.” In Act 17:18, it denotes an inferior pagan deity. “Demons” are the spiritual agents acting in all idolatry. The idol itself is nothing, but every idol has a “demon” associated with it who induces idolatry, with its worship and sacrifices, 1Cr 10:20, 21; Rev 9:20; cp. Deuteronomy 32:17; Isa 13:21; 34:14; 65:3, 11. They disseminate errors among men, and seek to seduce believers, 1Ti 4:1. As seducing spirits they deceive men into the supposition that through mediums (those who have “familiar spirits,” Lev 20:6, 27, e.g.) they can converse with deceased human beings. Hence the destructive deception of Spiritism, forbidden in Scripture, Lev 19:31; Deuteronomy 18:11; Isa 8:19. “Demons” tremble before God, Jam 2:19; they recognized Christ as Lord and as their future Judge, Mat 8:29; Luke 4:41. Christ cast them out of human beings by His own power. His disciples did so in His Name, and by exercising faith, e.g., Mat 17:20.

Acting under Satan (cp. Rev 16:13, 14), “demons” are permitted to afflict with bodily disease, Luke 13:16. Being unclean they tempt human beings with unclean thoughts, Mat 10:1; Mar 5:2; 7:25; Luke 8:27-29; Rev 16:13; 18:2, e.g. They differ in degrees of wickedness, Mat 12:45. They will instigate the rulers of the nations at the end of this age to make war against God and His Christ, Rev 16:14.


B-1 Verb Strong's Number: g1139 Greek: daimonizomai

Demon, Demoniac:

Signifies “to be possessed of a demon, to act under the control of a demon.” Those who were thus afflicted expressed the mind and consciousness of the “demon” or “demons” indwelling them, e.g., Luke 8:28. The verb is found chiefly in Matt. and Mark; Mat 4:24; 8:16, 28, 33; 9:32; 12:22; 15:22; Mark 1:32; 5:15, 16, 18; elsewhere in Luke 8:36; and John 10:21, “him that hath a devil (demon).”

C-1 Adjective Strong's Number: g1141 Greek: daimoniodes

Demon, Demoniac:

Signifies proceeding from, or resembling, a demon, “demoniacal;” see marg. of Jam 3:15, RV (text, “devilish”). (3)

Can a Christian be demon possessed? See below for link.

Not to fear:

“Ye are of God, little children, and have overcome them: because greater is he that is in you, than he that is in the world.” (1John 4:4)


1.            Matthew Poole's Commentary on the Holy Bible, Ephesians, Vol. 3. (Peabody, Massachusetts, Hendrickson Publishers, 1985) p. 679.

2.            H. D. M. Spence and Joseph S. Exell, The Pulpit Commentary, 1Timothy, Vol.21., (Grand Rapids, Michigan, Eerdmans Publishing Company reprint 1978), p. 68.

3.            W. E. Vine, An Expository Dictionary of New Testament Words, (Iowa Falls, Iowa, Riverside Book and Bible House), p. 283-284.

“To God, only wise, be glory through Jesus Christ forever. Amen.” (Romans 16:27) and “heirs according to the promise.” (Galatians 3:28, 29)

Mr. Kettler has previously published articles in the Chalcedon Report and Contra Mundum. He and his wife Marea attend the Westminster, CO, RPCNA Church.  He is the author of the book defending the Reformed Faith against attacks, titled: The Religion That Started in a Hat. Available at: www.TheReligionThatStartedInAHat.com

For more study:

* CARM theological dictionary https://carm.org/dictionary-hermeneutics

** https://www.gotquestions.org/demons-Bible.html

Satan Disarmed, Sin Forgiven, Soul Alive by John Piper https://www.desiringgod.org/articles/satan-disarmed-sin-forgiven-soul-alive

Can a Christian be demon possessed? https://www.gotquestions.org/Christian-demon-possessed.html