If we believe in God, we should also believe that demons exist. It would be foolish for a Christian to live a godly life without recognizing that demons are lurking around. Spiritual warfare is part of our walk with God. The Bible says that our true struggle is not against other men but against various dark forces—the devil and his demons, to be exact (Ephesians 6:12).
Demons are spiritual beings and have no physical bodies as humans do. Scripture does not describe what demons really look like. The only description in the Bible about the appearances of satan and his demons can be found in 2 Corinthians 11:14-15, where Paul said that they appear or masquerade as “angels of light.” They are, actually, angels that have fallen in with satan after rebelling against God (2 Peter 2:4 For if God spared not the angels that sinned, but cast them down to hell, and delivered them into chains of darkness, to be reserved unto judgment;). Some of the demons are now bound in eternal chains under darkness (Jude 1:6), while some still roam the earth with satan, spreading dark influence and destruction in varying ranks and scope (Ephesians 6:12 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.).
These demons are powerful beings. Along with satan, they have the capacity to inflict diseases (Acts 10:38), cause human disability (Matthew 12:22), initiate some natural and man-made calamities (Job 1), possess or influence humans (Mark 1:23; 5:2; 9:18) and animals (Mark 5:12-13), and even perform counterfeit signs and wonders through influenced humans (2 Thessalonians 2:9, 1 John 4:1). But their greatest and most effective power is deception. They may manifest in scary ways, but they are most efficient when they appear through subtle and seductive influence like an “angel of light.” A lot of men have fallen, even some godly ones, to satan and his demons’ temptations. This is their will—to steal, kill, and destroy (John 10:10). That’s why every Christian must be careful with the devil’s allure. We are warned not to give satan and his demons a foothold in our lives. Since they have a lot of influence in this world, we are urged to no longer conform to the patterns of this world but to let our minds be transformed by God’s will (Romans 12:2 And be not conformed to this world: but be ye transformed by the renewing of your mind, that ye may prove what is that good, and acceptable, and perfect, will of God.). There are some things we can learn from demons, though—they fear God, and they obey (Matthew 8:32, James 2:19); probably more than most humans do.
When it comes to the power of satan and his demons, our assurance is that they are very limited in power and authority. God is still in full control. They cannot go beyond what God’s sovereignty allows (Job 1). They are not all-knowing (omniscient), all-present (omnipresent), or all-powerful (omnipotent), unlike our God, as we learn in the book Job.
For those who have a relationship with God, we are not to fear them, but we are to fear God the most. Satan and all the demons’ power put together cannot come close to how powerful Christ is; it’s a mismatch. Read Mark 5:1-20, and you’ll see how they cower before Christ. If we have Christ, we have the greatest power against this dark world.
“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.”
(1 John 4:4 KJV)
By Christ’s sacrifice, we have triumphed over all the forces of darkness with Him.
“And you, being dead in your sins and the uncircumcision of your flesh, hath he quickened together with him, having forgiven you all trespasses; Blotting out the handwriting of ordinances that was against us, which was contrary to us, and took it out of the way, nailing it to his cross; And having spoiled principalities and powers, he made a shew of them openly, triumphing over them in it.”
(Colossians 2:13-15 KJV)