Christian Beliefs on the Devil and Demons

Jesus rebuked the demon, and it came out of the boy, and he was healed from that moment."
-- Matthew 17:18, NIV

"The demon threw him to the ground in a convulsion. But Jesus rebuked the evil spirit, healed the boy and gave him back to his father. And they were all amazed at the greatness of God."
-- Luke 9:42-3

"Your enemy the devil prowls around like a roaring lion looking for someone to devour. Resist him, standing firm in the faith."
-- 1 Peter 5:8-9
In Christian belief, angels were created good but were endowed with free will just as humans were. Some of them rebelled against God, were banished from heaven, and became demons. The English word "demon" derives from the Greek daemon (δαίμων), which originally referred to any spirit but came to be associated with only evil spirits.

In Christian teaching, the leader of the rebellious angels was Satan, who has became humanity's chief adversary. He is identified with the serpent who tempts Adam and Eve in Genesis.

In New Testament times, daemon had a number of meanings, all related to the idea of a spirit that inhabited a place or accompanied a person. Whether a daemon was benevolent or malevolent, the Greek word most meant something different from the later medieval notions of 'demon', and scholars debate the time in which first century usage by Jews and Christians in its original Greek sense became transformed to the later medieval sense.

There is a description in the Book of Revelation 12:7-17 of a battle between God's army and Satan's followers and their subsequent expulsion from Heaven to earth to persecute humans. In Luke 10:18 it is mentioned that a power granted by Jesus to control demons made Satan "fall like lightning from heaven."

Saint Augustine's reading of Plotinus, in City of God (ch. 11) is ambiguous as to whether daemons had become 'demonized' by the early 5th century:

"He (Plotinus) also states that the blessed are called in Greek eudaimones, because they are good souls, that is to say, good demons, confirming his opinion that the souls of men are demons." (City of God, ch. 11.—Of the Opinion of the Platonists, that the Souls of Men Become Demons When Disembodied)
In any case, the Catholic Church unequivocally teaches that angels and demons are real personal beings, not just symbolic devices of literature and myth (see Fr. John Corapi's article). The Catholic Church has a cadre of exorcists, who teach that demons attack humans and that Christ came to deliver us from Satan's evil rule by power in this fashion. According to the Catholic Church, demonically afflicted persons can be effectively healed and protected either by the formal rite of exorcism, authorized to be performed only by bishops and those they designate, or by prayers of deliverance which any Christian can offer for themselves or others.

Building upon the few references to demons in the New Testement, especially the visionary poetry of the Apocalypse of John, Christian writers of apocrypha from the 2nd century onwards created a more complicated tapestry of beliefs about "demons" that was independent of Christian scripture.

According to Christian mythology, When God created angels, he offered them the same choice he was to offer humanity: follow, or be cast apart from him. Some angels chose not to follow God, instead choosing the path of evil. One of these angels desired to be as powerful as God, and seduced a host of his companions to follow him against their ruler, to become himself the new sovereign. This rebellious angel was named Satan (lit. "adversary").

According to popular tradition, the fall of Satan is portrayed in Ezekiel 28:12-19 and Isaiah 14:12-14. Christian mythology built upon later Jewish traditions that Satan and his host declared war with God, but God's army, commanded by the archangel Michael (archangel), defeated the rebels. Their defeat was never in question, but Michael was given the honor of victory in the natural order. God then cast his enemies from Heaven to the abyss of the earth, into a newly created prison called Hell where all his enemies should be sentenced to an eternal existence of pain and misery. This pain is not all physical; for their crimes, these angels, now called demons, would be deprived of the sight of God (2 Thessalonians 1:9), this being the worst possible punishment.

An indefinite time later, when God created the earth and humans, Satan and the other demons were allowed to tempt humans or induce them to sin by other means. The first time Satan did this was in the earthly paradise or Garden of Eden to tempt Eve, who subsequently drew her husband Adam into her crime. Upon their failure, as part of the punishment, the permission granted to Satan and his demons to tempt the first humans away from their Creator will now last until the end of this world for all people.

According to Christian demonology demons will be eternally punished and never reconciled with God, as it is mentioned in the Bible. Other theories alleging the reconciliation of Satan, the fallen angels, the souls of the dead that were condemned to Hell, and God are not part of Christian demonology or literal scripture but the theory of the Unification Church. Origen, Jerome and Gregory of Nyssa mentioned this possibility before it was generally accepted that the fallen state is eternal.

In contemporary Christianity, demons are generally considered to be angels who fell from grace by rebelling against God. However, this view, championed by Origen, Augustine and John Chrysostom, arose during the 6th century. Prior to that time, the primary sin of fallen angels was considered to be that of mating with mortal women, giving rise to a race of half-human giants known as the Nephilim.

There are still others who say that the sin of the angels was pride and disobedience. It seems quite certain that these were the sins that caused Satan's downfall (Ezek. 28). If this be the true view then we are to understand the words, "estate" or "principality" in Deuteronomy 32:8 and Jude 6 ("And the angels which kept not their first estate, but left their own habitation, he hath reserved in everlasting chains under darkness unto the judgment of the great day.") as indicating that instead of being satisfied with the dignity once for all assigned to them under the Son of God, they aspired higher. {1}