Demons

What Demons Are

Scripture presents demons as fallen angels — spiritual beings originally created good who rebelled against God under Satan's leadership (see Jude 1:6's 'angels who didn't keep their first estate'). The Gospels most often call them 'unclean spirits' or simply demons, and consistently show them as real, personal, malevolent beings rather than a metaphor for illness or misfortune: they recognize Jesus's identity instantly and involuntarily ('I know you who you are: the Holy One of God!' Mark 1:24), they speak, they beg (Mark 5:10-12), and James notes flatly that even 'the demons... believe' God is one 'and shudder' (James 2:19) — correct theology without any of the trust or obedience that would make it saving faith.

Paul describes the wider spiritual conflict demons represent in cosmic terms: 'our wrestling is not against flesh and blood, but against the principalities, against the powers, against the world's rulers of the darkness of this age, and against the spiritual forces of wickedness in the heavenly places' (Ephesians 6:12) — framing the church's struggle as ultimately spiritual, with demonic forces organized under Satan's authority rather than acting as isolated, random troublemakers.

Demons Confronted in the Gospels and Acts

Casting out demons is one of the most frequently recorded acts of Jesus's ministry, presented as clear evidence of his authority over the spiritual realm. His most dramatic exorcism involves a man possessed by a demon who identifies himself, 'My name is Legion, for we are many' — so many that, once cast out at their own request, they enter a herd of about two thousand pigs, which immediately rush into the sea (Mark 5:1-13). Jesus explicitly ties his exorcisms to the arrival of God's kingdom: 'if I by the Spirit of God cast out demons, then God's Kingdom has come upon you' (Matthew 12:28), and he delegates the same authority to his twelve apostles (Matthew 10:1) and, later, to seventy-two other disciples, who return rejoicing that 'even the demons are subject to us in your name' (Luke 10:17). Acts continues this pattern into the early church: Paul casts a divining spirit out of a slave girl in Philippi (Acts 16:16-18), while the itinerant Jewish exorcists known as the sons of Sceva find, to their harm, that invoking Jesus's name without genuine faith in him carries no such authority at all (Acts 19:13-16).

Scripture references

• Mark 1:21-27 — Jesus casts an unclean spirit out of a man in the Capernaum synagogue
• Mark 5:1-20 — The Legion of demons cast into a herd of pigs
• Matthew 12:22-28 — Casting out demons as evidence God's Kingdom has come
• Luke 10:17-20 — The seventy-two return rejoicing that demons are subject to them
• Ephesians 6:12 — Paul frames the church's struggle as fundamentally spiritual
• Acts 19:13-16 — The sons of Sceva attempt exorcism without genuine faith in Jesus

Further reading

• Encyclopaedia Britannica: Demon
• Got Questions: What does the Bible say about demons?