The following is an outline from Wayne Grudem for chapter 20 of his book, Systematic Theology, dealing with Satan and Demons. There are three teachings on this chapter located elsewhere on this website.
Chapter 20: Satan and Demons: How should Christians think of Satan and demons today? Spiritual warfare.
Demons are evil angels who sinned against God and who now continually work evil in the world.
A. The Origin of Demons (p. 411)
1. Between the events of Gen 1:31 and 3:1, a rebellion in the angelic world must have taken place.(Gen. 1:31, 2Pe. 2:4, Jud 1:6) Language of ascending to heaven and setting his throne on high rebellion. (Isa. 14:12-15)
2. Angels are nonmaterial and do not marry casts doubt on idea that "the sons of God" = angels who married human wives. Likely that "sons of God" refers to people belonging to God and, like God, walking in righteousness. (Gen. 6:2, Mat 22:30, Deu 14:1, Gen 4:26, Cf. Gen. 5, 5:3)
B. Satan as Head of the Demons (414)
1. "Satan": head of the demons, God's enemy. (Job 1 :6, 1Ch 21:1, Zec 3:1, Luk 10:18)2. Other names for Satan: "The devil" (NT only) (Mat 4:1, Mat 13:39, Mat 25:41, Rev 12:9, Rev 20:2);"The serpent" (Gen 3:1, 2Co 11:3, Rev 12:9, Rev 20:2); "Be-elzebul" (Mat 10:25, Mat 12:24, Luk11:15); "The ruler of this world" (Joh 12:31, Joh 14:30, Joh 16:11); "The prince of the power of the air" (Eph 2:2); "The evil one" (Mat 13:19, 1Jo 2:13)
C. The activity of Satan and demons (p. 415)
1. Satan was the originator of Sin. (Gen 3:1-6, 2Co 11:3, Joh 8:44, 1Jo 3:8)2. Demons oppose and try to destroy every work of God. (Gen 3:1-6, Mat 4:1-11, Rev 12:9, Psa106:37, Joh 8:44, 2Co 4:4, Gal 4:8)
3. Yet demons are limited by God's control and have limited power. (Job 1:12, 2:6; Jud 1:6; Jam 4:7).Note: We should not think that demons can know the future/read our minds. God alone can know thefuture. (Isa 46:9-10, Mar 13:32; Mat 9:4, 12:25; Gen 6:5; Psa 139:2, 4, 23; Dan 2:27-28)
Note:Demons can observe what goes on in the world/probably draw conclusions from observations.
4. There have been differing stages of demonic activity in the history of redemption.
a. In the Old Testament (Deu 32:16-17, Psa 106:35-37, 1Co 10:20, 1Jo 5:19)i. No clear instance of casting out demons in Old Testament (1Sa 16:23)ii. Worship of demons will regularly lead to immoral and self-destructive practices (Psa 106:35-37, 1Ki 18:28, Deu 23:17)
b. Ministry of Jesus: Jesus' power over demons a distinguishing mark on his ministry to inauguratethe reign of the kingdom of God in new and powerful way. (Mat 12:28-29, Mar 1:27)
c. New Covenant Age: Authority over demonic powers given to the Twelve (Mat 10:8, Luk 10:17-18, Act 8:7, 1Pe 5:8-9, 1Jo 3:8)
d. During the Millennium: Activity of Satan/demons further restricted. (Rev 20:1-3, Rev 20:7-9)
e. At the Final Judgment: Satan will be decisively defeated (Rev 20:10)
D. Our Relationship to Demons (p. 419)
1. Are demons active in the world today? If Scripture gives us a true account of the world as it really is,we must take seriously its portrayal of intense demonic involvement in human society.
2. Not all evil and sin is from Satan/demons, but some is. (1Co 1:10, 1Co 5:1-5, 1Co 11:33, 1Co 11:28)
a. Occasionally Jesus or Paul would cast out a demonic spirit that was causing significant hindranceto proclaiming the gospel, but that is not the usual pattern of ministry presented. The emphasiswas simply on preaching the gospel (Mar 5:7-8, Mar 16:16-18, Mat 9:35, Rom 1:18-19)
b. God himself may reveal the nature of certain demonic opposition, which Christians would thenpray and battle against (1Co 12:10, 2Co 10:3-6, Eph 6:12)
c. Though NT clearly recognizes the influence of demonic activity in the world, its primary focus regarding evangelism and Christian growth=choices and actions taken by people (Gal 5:16-26)
d. NT authors were definitely aware of the presence of demonic influence in the world and in thelives of Christians (1Co 10:20, 1Ti 4:1, 2Ti 2:24-26, Joh 8:44 , 1Jo 3:8, 1Jo 5:19)
e. The emphasis of the NT is not on the influence of demons but on the sin that remains in thebeliever's life. Yet, sinning (even by Christians) does give a foothold for some kind of demonicinfluence in our lives. (Eph 4:26, Eph 6:11-12, 1Jo 5:18)
f. As these passages suggest, where there is a pattern of persistent sin in the life of a Christian, theprimary responsibility for that sin rests with the individual Christian. (Rom 6:12-16)
g. Nevertheless, there could possibly be some demonic influence contributing to and intensifyingthat sinful tendency.
3. Can a Christian be demon possessed?
a. The Greek NT never uses language that suggests a demon "possesses" someone. (Mat 11:18,Luk 7:33, Joh 7:20, Joh 8:48-49)
b. If "demon possessed" = person's will completely dominated by a demon, so that a person has nopower left to choose to do right and obey God, no. (Rom 6:14, Rom 6:4)
c. Most Christians would agree there can be differing degrees of demonic attack or influence in thelives of believers. (Luk 4:2, 2Co 12:7, Eph 6:12, Jam 4:7, 1Pe 5:8)
d. If a Christian does not know about or make use of the weapons of spiritual warfare, the degree ofdemonic attack could be quite strong.
4. How can demonic Influences be recognized?
a. Severe cases in the Gospels: bizarre and often violent actions, especially to the preaching of theGospel. (Mar 1:23-24, Mar 9:17-18, Mar 9:22, Mar 5:2-5)
b. Blatantly false doctrinal statements (1Co 12:3, 1Jo 4:2-3, 2Co 11:13-15)
c. Subjective sense of the presence of evil spiritual influence (1Co 12:10, 2Co 2:15-16)
d. Some degree of uncertainty in our perception of presence of demonic influence. (Jam 3:2)
5. Jesus gives all believers authority to rebuke demons and command them to leave. (Luk 9:1, Luk10:17, Luk 10:19, Act 16:18, 2Co 10:3-4, Eph 6:11-12, Jam 4:7, 1Pe 5:8-9)
a. Objection: Jude 9 teaches Christians should not command or rebuke evil spirits (Jud 1:8-10)
b. Because of Christ's death on the cross, our sins are completely forgiven, and Satan has norightful authority over us. (Heb 2:14, Col 2:15, Rev 12:11)
c. When Satan attacks us, he is attacking God's own children. (Gal 3:26)
d. Satan and demons have much less power than the power of the Holy Spirit not need to be afraid (1Jo 4:4, 2Ti 1:7, Phi 1:28, Eph 6:16, 2Co 10:4, 1Jo 5:18)
e. Speak directly to the demon rather than just praying and asking God to drive it away? (Jam 4:7,Eph 6:17, Mat 4:4, Mat 4:7, Mat 4:10, 2Co 10:3-4)
f. For unusually strong sinful emotions, it is appropriate to say something like, "Spirit of fear, inJesus' name, I command you, go away from here and don't return!" (Eph 6:12, 2Co 10:3)
g. Times of intercessory prayer may include an element of verbal rebuke to demonic forces thatmay be a component in situations for which we are praying.
6. Appropriate use of the Christian's spiritual authority in ministry to other people.
a. Important not to frighten people by talking glibly about an area familiar to us but frightening toothers. (1Co 14:3)
b. If given permission, a brief command should be spoken aloud, telling the spirits to leave. (Thisdoes not have to be highly dramatic or emotionally charged.) (Mat 8:16, Luk 8:30, Mat 12:28)
c. Focus not on the demon but on the person being ministered to and the truths of the Bible that need to be affirmed or believed. (Eph 6:14, Eph 6:17)
d. Important that believers not become overly curious of demonic conflict (1Co 14:20)
e. For non-believers ministered to: important he or she be urged to come to Christ as Saviorimmediately after demon is cast out. (Mat 12:43-45)
f. Effectiveness in difficult cases of demonic influence related to our own spiritual condition. (Mat17:18-20, Mar 9:29)
g. We should not rejoice too much or become proud in power over demons but rejoice in our greatsalvation (Luk 10:20)
7. We should expect the Gospel to come in power to triumph over the works of the devil. (Luk 4:41,Act 8:7, 1Co 2:4-5, 2Co 10:3-4, 1Jo 3:8)