Seven princes of Hell

There have been various attempts throughout history by theologian scholars in the classification of demons for the purpose of understanding the biblical and mythological context of adversarial spirits. Theologians have written dissertations in Christian demonology, classical occultism, classical mythology and Renaissance magic to clarify the connections between these spirits and their influence in various cultures. The study of demonology was historically used to understand morality, behavioral tendencies, and has even been used as symbolism to relay anecdotal tales in folklore. Classification systems are based on the supposed nature of the demon, the alleged sin with which they lure people into temptation and may also include the angels or saints that were believed to have been their adversaries; an idea which derived from the Biblical battle between the Archangel Michael and Satan in The Book of Revelation () describing a war in heaven which resulted in Satan and his angels being expelled from Heaven. The classifications of these fallen angels are based on many other characteristics as well, such as behaviors that caused their fall from heaven, physical appearances or the methods that were used to torment people, cause maladies, or illicit dreams, emotions, etc. Most authors who wrote theological dissertations on the subject either truly believed in the existence of infernal spirits, or wrote as a philosophical guide to understanding an ancient perspective of behavior and morality in folklore and religious themes.

In the study of demonology, infernal spirits are often classified by domain, meaning their attribution to a specified sphere of activity or knowledge. Often times this means a specific moral sin or questionable behavior to which some people are prone. They may even be attributed to the methods they cause trouble to humans by the use of certain misfortunes, maladies, or addictions. In general, the domain of a demon is reflected on whatever authority they hold in their interaction with mankind. This idea holds a similar connotation to the gods of classical mythology as each have their own tasks and abilities according to their authority and each interact with mankind in their own unique way. It can be noted that according to each author listed below, the domain of each demon is varied greatly on either preference or perspective. It can also be seen that each author chooses and classifies demons differently based on their own personal set of beliefs or politics.

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