The History of Demonology is one that is quite unclear before 1160 B.C. But writings from 1170 B.C. states that Magic was first conceived in a city called Persida and that a Nomad named Klingsor traveled there and brought back with him the art of Magically effecting whatever he wished. When Klingsor found the strength of his true powers he began to brag about how sly and cunning he was to get women into bed, but that served him no justice after he got caught sleeping with the kings wife (The Queen). Klingsor was castrated and turned into a Eunuch and never again looked favorably upon man nor woman again, he enjoyed seeing other people suffer and that was the only thing that gave him great joy. This was one of the first recorded examples of the weak becoming empowered by sacrificing themselves to the Devils and Demons in exchange for sweet revenge. We find the word Magic used above simply because any time you entered into the world of conjuring or summoning evil or dark forces that is what it was called, later threw the centuries magic took on many forms like Elemental, White, Dark, Black, Etc and then Demononology was given it's own Category.
In a more specific sense, we should be aware of particular activities carried out by demons. For instance a demon can control and inflict physical maladies like dumbness, muteness, deafness, epilepsy and personal injury. Demons can cause suicide, they can give great physical strength, they can possess animals, cause men to worship demons, promote false doctrine and oppose the spiritual growth of believers. They even attempt to separate believers from the love of God, and to take control of all from within. But not all physical maladies are caused by demons. There is a distinction between physical problems caused by human frailty, illness and those caused by demons. Demonic control, sometimes inaccurately called demonic possession, must be defined. The Greek daimonizomai means "to be demonized" emphasizing control rather than possession, in fact, the Greek word for possession is never used in conjunction with demons. We must realize that the original Greek though commonly translated as possessed by a demon, implying ownership is much more accurately translated to mean controlled by a demon.
Wow, we serve an awe-some God, the Lord Jesus Christ. 
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