1. Systematic Theologians either Disagree or Remain Silent
1.1. Demon Possession
1.1.1. Incidents of demon possession are given prominent attention in the biblical accounts. The technical expression is to “have a demon” (δαιμόνιον ἔχω—daimonion echō) or to “be demonized” (δαιμονίζομαι—daimonizomai). Sometimes we find expressions like “evil spirits” (Acts 8:7; 19:12). Millard J. Erickson, Christian Theology, 3rd ed. (Grand Rapids, MI: Baker Academic, 2013), 418.
1.2. Identity of Good cf. Evil Angels
1.2.1. Where to consider the topic of evil angels presents a problem. Dealing with them in connection with our examination of good angels would tend to suggest a parallel. Since the good angels have been treated at this point because of their obvious relationship to divine providence, are not the evil angels or demons rather out of place here? Would it not be more appropriate to handle this topic in connection with our study of sin? But discussing the evil angels at this point is justified on two grounds. First, the evil angels should be studied in close connection with the good angels since they have the same derivation, and much of what has been said about the latter is true of the former as well. The good angels are still what the evil angels once were. Second, the providence of God has about it the shadow of the problem of evil. Since we have just discussed evil, it seems appropriate to treat the subject of demons and the devil here. We will refer to these evil agents again when we discuss sin and temptation, and when we delve into the doctrine of the last things; but they simply cannot be ignored at this present juncture. Millard J. Erickson, Christian Theology, 3rd ed. (Grand Rapids, MI: Baker Academic, 2013), 415.
1.2.2. What is their origin
1.2.2.1. The Bible has little to say about how evil angels came to have their current moral character and even less about their origin. We may learn something about their origin from what is said about their moral character. Two closely related passages inform us regarding the fall of the evil angels. Second Peter 2:4 says that “God did not spare angels when they sinned, but sent them to hell, putting them in chains of darkness to be held for judgment.” Jude 6 says that “the angels who did not keep their positions of authority but abandoned their proper dwelling—these he has kept in darkness, bound with everlasting chains for judgment on the great Day.” The beings described in these two verses are clearly identified as angels who sinned and came under judgment. They must, like all the other angels, be created beings. A problem presented by these verses is that the evil angels are said to have been cast into nether gloom to be kept until the judgment. This has led some to theorize that there are two classes of fallen angels: those who are imprisoned, and those who are free to carry on their evil in the world. Another possibility is that these two verses describe the condition of all demons. That the latter is correct is suggested by the remainder of 2 Peter 2. In verse 9 Peter says that “the Lord knows how to rescue the godly from trials and to hold the unrighteous for punishment on the day of judgment.” This language is almost identical to that used in verse 4. Note that the remainder of the chapter (vv. 10–22) is a description of the continued sinful activity of these people who are being kept under punishment. We conclude that, similarly, though cast into nether gloom, the fallen angels have sufficient freedom to carry on their evil activities. Millard J. Erickson, Christian Theology, 3rd ed. (Grand Rapids, MI: Baker Academic, 2013), 416.
1.2.2.2. How does God Use Demons in His Sovereignty
1.2.2.2.1. Demons, then, are angels created by God and therefore were originally good; but they sinned and thus became evil. Just when this rebellion took place we do not know, but it must have occurred between the time when God completed the creation and pronounced it all “very good,” and the temptation and fall of the humans (Gen. 3). Millard J. Erickson, Christian Theology, 3rd ed. (Grand Rapids, MI: Baker Academic, 2013), 416.
1.3. Demon Activities and Limitations of Power
1.3.1. As Satan’s subjects, demons carry out his work in the world. It may therefore be assumed that they engage in all the forms of temptation and deception he employs. They inflict disease: dumbness (Mark 9:17), deafness and dumbness p 418 (Mark 9:25), blindness and deafness (Matt. 12:22), convulsions (Mark 1:26; 9:20; Luke 9:39), and paralysis or lameness (Acts 8:7). Most particularly, they oppose the spiritual progress of God’s people (Eph. 6:12) Millard J. Erickson, Christian Theology, 3rd ed. (Grand Rapids, MI: Baker Academic, 2013), 417–418.
1.4. To whom do Demon's Boss and what is the Ultimate Goal?
1.4.1. “The devil” is the name given in Scripture to the chief of these fallen angels. He is also known as Satan. The Hebrew name שָׂטָן (satan) derives from the verb שָׂטַן (satan), which means to be or act as an adversary.22 Hence he is the opponent, the one who opposes the cause and the people of God. The Greek word Σατᾶν (satan) or Σατανᾶς (satanas) is a transliteration of this Hebrew name. The most common Greek word for him is διάβολος (diabolos—devil, adversary, accuser). κατήγωρ (katēgōr—accuser—Rev. 12:10) is also used. Several other terms are used of him less frequently: tempter (Matt. 4:3; 1 Thess. 3:5), Beelzebul (Matt. 12:24, 27; Mark 3:22; Luke 11:15, 19), enemy (Matt. 13:39), evil one (Matt. 13:19, 38; 1 John 2:13; 3:12; 5:18), Belial (2 Cor. 6:15), adversary (1 Pet. 5:8), deceiver (Rev. 12:9), great dragon (Rev. 12:3), father of lies (John 8:44), murderer (John 8:44), sinner (1 John 3:8). All of these convey something of the character and activity of the devil. Although the devil is not explicitly termed a demon in Scripture, Jesus identified Satan with Beelzebul, the prince of demons (see the parallel accounts in Matt. 12:22–32; Mark 3:22–30; and Luke 11:14–23). That Satan is a demon is also implied in Luke 10:17–20, where the casting out of demons signals the defeat of Satan. Those who were demon-possessed were characterized as “under the power of the devil” (Acts 10:38; cf. Luke 13:16). Millard J. Erickson, Christian Theology, 3rd ed. (Grand Rapids, MI: Baker Academic, 2013), 417.
1.4.2. If Satan and the Demons know they are defeated in the Eschaton, why do they Persist?
1.4.2.1. The Bible makes clear that a serious and intense struggle is going on between, on the one side, Christ and his followers and, on the other, Satan and his forces. Evidences of the struggle include the temptation of Jesus (Matt. 4:1–11), Jesus’s encounters with demons, and numerous other passages (e.g., Luke 22:31–34; Gal. 5:16–17; Eph. 6:10–20). The temptation of Jesus represented a preliminary victory over Satan. Other anticipations of the final victory are found in Luke 10:18; John 12:31; 14:30; 16:11; Romans 16:20; Hebrews 2:14–15; 1 John 2:13; 3:8; 5:18. Revelation 12 pictures a war in heaven between, on one side, Michael and his angels and, on the other, Satan and his angels, a war that results in Satan’s being thrown down from heaven to earth, and then attacking Christ and the church. In Revelation 20 we read that Satan will be bound for a thousand years (v. 2) and then released for a time before being cast into the lake of fire and brimstone forever (vv. 7, 10). Jesus indicates that this will also be the fate of Satan’s angels (Matt. 25:41). The decisive battle in the war between good and evil was fought and won by Christ in the crucifixion and resurrection. Satan has been defeated, and although he continues to fight on desperately, his fate has been sealed. Christians can take comfort in the realization that they need not be defeated in any of their specific encounters with Satan (1 Cor. 10:13; 1 John 4:4). Millard J. Erickson, Christian Theology, 3rd ed. (Grand Rapids, MI: Baker Academic, 2013), 419.