“All practices of magic or sorcery, by which one attempts to tame occult powers, so as to place them at one's service and have a supernatural power over others — even if this were for the sake of restoring their health — are gravely contrary to the virtue of religion. These practices are even more to be condemned when accompanied by the intention of harming someone, or when they have recourse to the intervention of demons. Wearing charms is also reprehensible. Spiritism often implies divination or magical practices; the Church for her part warns the faithful against it. Recourse to so-called traditional cures does not justify either the invocation of evil powers or the exploitation of another’s credulity.” (Catechism of the Catholic Church, number 2117).
Thus, while the Church recognises the existence of ghosts, Catholics are not to intentionally seek them out — for good or for ill. Another theory about ghosts is that these spectres are actually a space-time-continuum replay of events that have happened in the past. This theory is possible, and is the most likely one that could fit into the belief system of the majority of Christians. Finally, there is always the strong risk that a "ghost" might, in fact, be a demon masquerading as a departed soul to torment and deceive the living. The Catholic Church unequivocally teaches that angels and demons are real personal beings, not just symbolic devices. The Catholic Church has a cadre of officially sanctioned exorcists who perform many exorcisms each year. These exorcists teach that demons attack humans continually but that afflicted persons can be effectively healed and protected either by the formal rite of exorcism, authorised to be performed only by bishops and those they designate, or by prayers of deliverance which any Christian can offer for themselves or others.
In contemporary Christianity, demons are generally considered to be angels who fell from grace by rebelling against God. However, other schools of thought in Christianity or Judaism teach that demons, or evil spirits, are a result of the sexual relationships between fallen angels and human women. When these hybrids (Nephilim) died they left behind disembodied spirits that "roam the earth in search of rest" (Luke 11: 24). Many non-canonical historical texts describe in detail these unions and the consequences thereof. This belief is repeated in other major ancient religions and mythologies. Christians who reject this view do so by ascribing the description of "Sons of God" in Genesis 6 to be the sons of Seth (one of Adam's sons).
In religion and mythology, occultism and folklore, a demon (or daemon, daimon; from Greek δαίμων daimôn) is a supernatural being that is generally described as a malevolent spirit.
In the Gospel of Mark, Jesus casts out many demons, or evil spirits, from those who are afflicted with various ailments. Jesus is far superior to the power of demons over the beings they inhabit, and He is able to free these victims by commanding and casting out the demons, by binding them, and forbidding them to return. Jesus also lends this power to some of His disciples, who rejoice at their new found ability to cast out demons.
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By way of contrast, in the book of Acts a group of Judaistic exorcists known as the sons of Sceva try to cast out a very powerful spirit without believing in or knowing Jesus, but fail with disastrous consequences. Jesus, on the other hand, never fails to vanquish a demon; irrespective of how powerful the demon might be (see the account of the demon-possessed man at Gerasim); and even defeats Satan in the wilderness (see the Gospel of Matthew).
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 (although this event is related as being foretold and taking place in the future). In Luke 10: 18 it is mentioned that a power granted by Jesus to control demons made Satan "fall like lightning from heaven."
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