Satan or the Devil is the embodiment of evil, and plays a major role in Christian theology and literature, as well as in many other religions. He is the tempter and spiritual enemy of mankind. He is the adversary of God, although subordinate to him and able to act only by his sufferance, and is represented frequently as the leader or prince of all apostate angels and as ruler of hell. "Satan is the force that loves to find the guilt and weakness in people, to humiliate them with it, to convince them that, because they are not good, God cannot love them." Leftist Saul Alinsky dedicated to Lucifer his book Rules for Radicals, which inspired some liberal activists.
Satan was once a member of the divine council of God referenced in the Old Testament. He is referenced 11 times in Job and 4 other times in the Old Testament. The New Testament mentions Satan 34 times in all, starting with the first book Matthew and ending with the last Revelation. In the Christian tradition he rebelled against God and is now the enemy of God and man alike. He is the father of lies and no good is found in him. He leads a host of fallen angels (or demons) who know their days are numbered before they will be cast in the lake of fire and they seek to take as many humans as possible with them.
In Christian theology Satan's goal is to lead people away from the love of God, by tempting or tricking them. The only sources of supernatural power in the world are from either God (good) or Satan (evil). In the book of Genesis, Satan takes the form of a snake and tempts Eve with fruit from a tree. This causes sin to come into the world. Kelly (2006) demonstrates how assumptions—such as the identification of the Eden serpent with Satan, probably first made by Justin Martyr in the second century—have hardened into fact.
Satan, in the Book of Job, listens to God speak highly of Job and accuses Job to God before the host of angels that Job praises God only because he is blessed and would curse God if he was forced to suffer. God allows Satan to do what he will except to spare his life, and Satan causes Job to suffer immensely. (Job remained true to God through his hardships; Satan accused him further and punished him further, but could not get Job to break).
Jesus makes references to demonic possession on multiple occasions that He then casts out. Some believe that Satan is able to possess and control living humans on Earth even today. Even more, some others believe that Satan actually has done this in the past as well. Specifically, Satan is said to have entered Judas during The Last Supper (John 13:27). The Catholic church believes that priests (and sometimes only bishops) are able to exorcise this possession through Jesus.
The word Satan derives from the Hebrew "ha-satan", meaning the "accuser", "tempter", "persecutor", "calumniator", or "adversary". He "was a liar and a murderer from the beginning." (John 8:44) Synonyms include Lucifer, demon, Mephistopholes, Mephisto, Beelzebub, the Evil One, the Tempter, and The Prince of Darkness. Only "devil" is used as an epithet for a profoundly evil person.
The adjectives include "devilish," "demonic", and "diabolic". Those who worship Satan are called Satanists, Satan-worshippers, or demonists.
Lucifer is a name literally meaning "Son of the Morning" (or "Light-Bearer"), and is mentioned in the Bible only in the book of Isaiah (Isaiah 14:12). Though in Christian tradition Lucifer is equated with Satan, the immediate context of the passage is Isaiah's prophecy against the king of Babylon, and the name "Lucifer" was not present at all in the original manuscripts (in the Latin Vulgate, the phrase "Son of the Morning" was transliterated as a proper name).
Whomever Lucifer may be, the Isaiah makes strong prophecy against him, condemning him for 5 pronouncements:
- I will ascend into heaven
- I will exalt my throne above the stars of God
- I will sit also upon the mount of the congregation, in the sides of the north
- I will ascend above the heights of the clouds
- I will be like the most High
Those who take this passage to be a reference to Satan believe that it gives more history of what caused his downfall, that he was created by God as one of His most powerful angels (possibly a Seraph), but that he fell from grace after he in his pride rebelled against his Creator. Some, however, believe that there is no grounding to interpret the passage as a history of Satan, citing that the passage uses highly figurative and poetic language that was meant as a prophecy against Babylon and nothing more.
In the Jewish tradition, Satan is an angel who faithfully serves God as a prosecuting attorney — one who accuses men of wickedness and impiety. At the direction of God, Satan may be permitted to test these accusations, such as in Job. In this view, Satan's goal is not to lead men away from their faithfulness to God, but merely to reveal the true depths of their devotion, although in I Chronicles 21:1 Satan provoked David to take a census of the people of Israel against the will of God and 70,000 men are slain because of it. II Samuel 24:1 supports the view of Satan as God's prosecuting attorney by reporting that it was the Lord Who moved David to take the census; the two passages can easily be reconciled if Satan acted as God's agent.
Jehovah's Witnesses believe that Satan was at one time an Angel who lived among the many millions of Angels that existed before the world was created. They believe that at some point He developed the desire to be worshiped by Humans and other Angels and so set himself in Opposition to worship of Jehovah, his God and Father. This they believe occurred in the Garden of Eden, and not prior to the Earths creation. Jehovah's Witnesses teach that Satan used a serpent as his mouth piece, the same way a vantriloquist uses a dummy, to bring the first Human couple under his control.
Jehovah's Witnesses teach that God has allowed Satan to rule mankind for several resons such as:
- Satan has challenged God's Right to rule his creations, not his power....
- Satan accuses God of bribeing Humans for their loyalty with protection and blessings....
- Satan has accused Humans of being loyal to God out of selfish reasons....
- Satan claims that he can rule mankind better than God....
Jehovah's Witnesses teach also that God decided that time, rather than a display of force, is needed to settle these issues. This, they believe, has giving Satan thousands of years to prove that Mankind is better off without God, that He (Satan) can rule Mankind successfully, and that the Humans that Do serve God do so only out of selfish reasons.
Jehovah's Witnesses teach that Satan does not live in any kind of Hell or world of the dead, but on the Earth as it's current ruler, along with as many as a third of the Angels of Heaven. They teach that Satan had lived in Heaven up until 1914, when Jesus and his Angels cast him out of Heaven, bringing woe to the Earth. this is their reasoning on Why the world has experienced two World wars, increasing lawlessness, an increase in disease and pollution, and the overall conditions on earth today.
Jehovah's Witnesses believe that Satan delegates authority to each Demon as he see's fit, and over what he see's fit, sometimes including whole Nations and kingdoms. They believe that Satan and his demons are in every way the enemy of God, rather than working alongside him. They teach that Satan will continue to rule the world until Armageddon, when Jesus Christ and his heavenly Angels come to earth and bind him, eventually killing him, freeing the world of all opposition towards True worship.
The three classic defenses against Satan are:
- mockery, which Satan cannot withstand due to his pride
- sunlight or exposure, from which Satan hides
- the Holy Spirit, meaning "The Advocate" (i.e., defense lawyer), or the Armor of God.
Note that Satan lacks self-restraint, which often leads him to failure. In addition, Satan delights in deceit, even to the point of causing his downfall.
Dante and Milton
The classic literary depictions of Satan appear in Dante's Italian poem, "Inferno," and in John Milton's English poem, "Paradise Lost." These are considered the two greatest poems in Italian and English literature.
In western art and popular culture the devil is used to represent evil influences or motivations.
Similarity to Prometheus
Some writers have pointed out that a few popular depictions of Satan are similar to that of Prometheus. 
- Caldwell, William. "The Doctrine of Satan: I. In the Old Testament," The Biblical World, Vol. 41, No. 1 (Jan., 1913), pp. 29–33 in JSTOR
- Caldwell, William. "The Doctrine of Satan: II. Satan in Extra-Biblical Apocalyptical Literature," The Biblical World, Vol. 41, No. 2 (Feb., 1913), pp. 98–102 in JSTOR
- Caldwell, William. "The Doctrine of Satan: III. In the New Testament," The Biblical World, Vol. 41, No. 3 (Mar., 1913), pp. 167–172 in JSTOR
- Empson, William. Milton's God (1966)
- Jacobs, Joseph, and Ludwig Blau. "Satan," The Jewish Encyclopedia (1906) online pp 68–71
- Kelly, Henry Ansgar. Satan: A Biography. (2006). 360 pp. excerpt and text search ISBN 0-521-60402-8, a study of the Bible and Western literature
- Kent, William. "Devil." The Catholic Encyclopedia (1908) Vol. 4. online older article
- Osborne, B. A. E. "Peter: Stumbling-Block and Satan," Novum Testamentum, Vol. 15, Fasc. 3 (Jul., 1973), pp. 187–190 in JSTOR on "Get thee behind me, Satan!"
- Rebhorn Wayne A. "The Humanist Tradition and Milton's Satan: The Conservative as Revolutionary," Studies in English Literature, 1500-1900, Vol. 13, No. 1, The English Renaissance (Winter, 1973), pp. 81–93 in JSTOR
- Russell, Jeffrey Burton. The Devil: Perceptions of Evil from Antiquity to Primitive Christianity (1987) excerpt and text search
- Russell, Jeffrey Burton. Satan: The Early Christian Tradition (1987) excerpt and text search
- Russell, Jeffrey Burton. Lucifer: The Devil in the Middle Ages (1986) excerpt and text search
- Russell, Jeffrey Burton. Mephistopheles: The Devil in the Modern World (1990) excerpt and text search
- Russell, Jeffrey Burton. The Prince of Darkness: Radical Evil and the Power of Good in History (1992) excerpt and text search
- Schaff, D. S. "Devil" in New Schaff-Herzog Encyclopedia of Religious Knowledge (1911), Mainline Protestant; vol 3 pp 414–417 online
- Scott, Miriam Van. The Encyclopedia of Hell (1999) excerpt and text search comparative religions; also popular culture
- Wray, T. J. and Gregory Mobley. The Birth of Satan: Tracing the Devil's Biblical Roots (2005) excerpt and text search
- The Rite Stuff: Satan as Prosecutor - Mike Potemra
- Ephesians 6:1-17
- Werblowsky, Raphael Jehudah Zwi. Lucifer and Prometheus: A Study of Milton's Satan. Routledge, reprinted 1999 and 2001; originally published 1952.
- The accuser of the brethren - commentary on Revelation 12:7-12 - Dr. J.B. Buffington