Demon

In religion, folklore, and mythology a demon or demoness is a supernatural being that has generally been described as a malevolent spirit, daemon (Greek: daimonion) and djinn (Genie (Arabic: jinni; variant spelling djinni) or jinn is a supernatural creature in Arab folklore and Islamic teachings which occupies a parallel world to that of mankind). A demon is frequently depicted as a force that may be conjured and insecurely controlled. The "good" demon in recent use is largely a literary device (eg: Maxwell's demon). In common language, "demonizing" one's opponent is an aspersion.

The Greek conception of a daemon (δαμων) appears in the works of Plato and many other ancient authors, but without the evil connotations which are apparent in the Septuagint translation of the Hebrew Bible and in the Greek originals of the New Testament. The medieval and neo-medieval conception of a "demon" in Western civilization (see the Medieval grimoire called the Ars Goetia) derives seamlessly from the ambient popular culture of Late (Roman) Antiquity: Greco-Roman concepts of daemons that passed into Christian culture are discussed in the entry daemon. The Hellenistic "Demon" eventually came to include many Semitic and Near Eastern gods as evaluated by Christianity.

The Greek daµµa daimonizomai (Matthew 8:28, Mat 8:33, Mat 9:32, Mar 5:15, Luk 8:36, etc) means "to be under the power of a demon." The Greek word daµ daimonion meaning "evil spirits or the messengers and ministers of the devil."

According to a Jewish opinion which passed over to Christians, the demons are the gods of the gentiles and the authors of idolatry, hence:

¹⁷ They sacrificed to demons that were no gods, to gods they had never known, to new gods that had come recently, whom your fathers had never dreaded.
—Deut. 32:17

The idea of demons is as old as religion itself, and the word "demon" seems to have ancient origins. The Merriam-Webster dictionary gives the etymology of the word as Greek daimon, probably from the verb daiesthai meaning "to divide, distribute." The Proto-Indo-European root *deiwos for god, originally an adjective meaning "celestial" or "bright, shining" has retained this meaning in many related Indo-European languages and cultures (Sanskrit deva, Latin deus, German Tiw), but also provided another other common word for demon in Avestan daeva.

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John Piper - Demonic power and indwelling sin

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