There are two primary issues to address regarding spiritual warfare and the Bible. First, does spiritual warfare exist? Second, what does the Bible say about engaging in spiritual warfare?
Spiritual warfare - What does the Bible say?
The Bible is very clear on the existence of spiritual warfare. Peter warns "Be sober-minded; be watchful. Your adversary the devil prowls around like a roaring lion, seeking someone to devour" (1 Peter 5:8). Our adversary or enemy, the devil, refers to Satan, who is a real entity, not a mythical creature or invention. Other titles of Satan include the tempter (1 Thessalonians 3:5), the wicked one (Matthew 13:19, 38), and the accuser of the brethren (Revelation 12:10).
Three of Satan's titles indicate his authority in this world: the ruler of this world (John 12:31), the god of this age (2 Corinthians 4:4), and the prince of the power of the air (Ephesians 2:2). Satan also transforms himself into "an angel of light," a description that highlights his capacity and inclination to deceive (2 Corinthians 11:14).
Spiritual warfare, the idea that humans battle in some way with supernatural powers, is also the testimony of the apostle Paul in Ephesians 6:10-18. Here, Paul notes that believers battle against the devil's schemes and that this is a spiritual battle, not a physical one. We are to be fully aware of Satan's evil plans (2 Corinthians 2:11). Paul further describes the warfare in which we are engaged as we battle throughout our lives "against the rulers, against the authorities, against the cosmic powers over this present darkness, against the spiritual forces of evil in the heavenly places" (Ephesians 6:12). Clearly, such powers exist.
The second question—what does the Bible say about engaging in spiritual warfare?— is somewhat more controversial. The problem typically arises when we either over emphasize spiritual warfare by seeing every occurrence in life as part of it or under emphasizing it by ignoring the spiritual realm altogether.
Several biblical texts inform our understanding of this issue. First, Christians must remember we are already conquerors (Romans 8:37) and that Satan has already been defeated (Colossians 2:15; 2 Peter 3:22). Second, the power of Christ within the believer is greater than the power of Satan (1 John 4:4). We have no reason to live in fear of Satan or evil spirits as believers. Satan can harm, but he cannot defeat the believer in Christ.
Third, we must not forget that Satan can be allowed to attack believers (2 Corinthians 12:7-9; James 1:2-4) in order to fulfill God's perfect plan for His people. This was the case of Paul's thorn in the flesh and was also seen in the example of Job's life (Job 1–3). Satan's power over us is limited, however, to only that which God ordains for His purposes—to bring His children to maturity and bring glory to Himself.
Fourth, Satan's primary strategy is to blind us to God's plan for our lives (2 Corinthians 4:3-4). Rather than a supernatural battle between angels and demons that is often portrayed in modern culture, the general tactic used by Satan is to turn our eyes away from God's truth and toward self. However, we cannot blame every temptation on Satan, since the Bible also teaches that we are tempted and enticed by our own evil desires (James 1:13-15).
Fifth, the method to defeat Satan is to resist him and stay near to God. James 4:7-8 instructs, "Submit yourselves therefore to God. Resist the devil, and he will flee from you. Draw near to God, and he will draw near to you." A close walk with God is the best protection against Satan's activities.
Sixth, Paul exhorts us to arm ourselves for the spiritual battle which is part of the Christian life by putting on the "whole armor of God, that you may be able to stand against the schemes of the devil" (Ephesians 6:11). This armor includes truth, righteousness, the gospel, faith, salvation, the Word of God, and prayer. These weapons will enable us to "be strong in the Lord and in the strength of his might" (Ephesians 6:10-18).
Ultimately, spiritual warfare is not about a technique to defeat Satan or demons, but a heart that walks closely with God. When God is first and foremost in our lives, Satan lacks power over us, despite his attempts to weaken our efforts to pursue Christ.
As a final warning, it is important that we do not take our God-given power over Satan as an opportunity to display arrogance. In Acts 19:13-16, we find the account of Jewish leaders who attempted to use God's power to overcome evil for their own benefit and received a harsh punishment for doing so. This stern warning should reveal our need to depend on a humble and personal walk with Christ to overcome evil rather than an external display to feed human pride.
In summary, spiritual warfare is a very real part of the Christian life, but should not be an opportunity for either fear or pride. Instead, the reality of Satan and his evil forces should cause us to draw near to God all the more, realizing His power can conquer any foe we may encounter.
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What is the sword of the Spirit?
Why does God allow Satan and the demons to attack us?
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Truth about the Christian Life