I realized today that I forgot to write up some thoughts in response to Hannah's question a week or two ago about "Lucifer." So here I go!

The first thing to make plain is that there is *not* a lot of data in the Bible about Satan's backstory or anything else about angels/demons. Those beings are purely "supporting characters" in the Bible's narrative, which is principally about God, man, sin, and redemption.

That being said, there are a few bits and pieces which we might stitch together to get a "Satan is a fallen angel" doctrine. The most explicit NT reference is Revelation 12:7-9. It speaks of Satan as a great dragon, who fought alongside "his angels" against the angels of God. Satan and his angels were thrown down in defeat as a result of this battle. The implication seems to be that Satan was once himself an angel, and that he was able to convince some of the other angels (perhaps one-third of them, if 12:4 is to be taken literally) to rebel against God and join him. (Btw, these verses also likens Satan to a "serpent," which is principally why the talking serpent in Genesis 3 has been traditionally associated with the devil.)

The two OT passages which may refer to Satan's fall are Isaiah 14:3-20 and Ezekiel 28:11-19. In both cases, the prophets are condemning the arrogant reigns of human monarchs (the kings of Babylon, and of the city of Tyre, respectively) but during their poetic rebukes of these men they seamlessly migrate to speaking of a superhuman, and evil, being. Not all scholars agree that these passages are talking about the devil, but most do. The consensus seems to be that the wicked human kings reminded the prophets of a greater wicked force that predated them and perhaps inspired them. Imagine writing a scathing treatise on Adolf Hitler, and while you're calling him out you are reminded again and again of the original evil supernatural beings who ultimately inspired Hitler and all tyrants, and so your verbiage wanders into speaking of those superhuman being. That's the flavor of the Isaiah and Ezekiel passages.

In all these cases, pride is central to the devil's downfall. The main message is that a beautiful, wise, and strong heavenly being got too full of himself and wanted to be equal to, or superior to, God, and was thence cursed by God and hurled down out of heaven.

By the way, in Isaiah 14:12, some English versions translate the wicked being's name as the English phrase "morning star," while others transliterate it to the proper name "Lucifer." This is where we get the idea that "Satan was originally called Lucifer." The name itself means something like "one who bears/shines light," so you can see why "morning star" is an apt translation. The name "Satan," as you may know, means "one who accuses," which is a big part of his M.O. in our world. More than anything, Satan desires to interrupt or even defeat our redemption through Christ, and so he goes all out to speak loudly of the things we've said and done that are unrighteous. Jesus, meanwhile, puts him to shame by His work on the Cross, which canceled all that unrighteousness once and for all. (So don't believe Satan! Hint: he's lying.)

One last thing before I sign off: don't ever lose sight of the fact that no matter how we might interpret these challenging verses, Satan is *not* in any way equal to God. He is a created being, and just like all other created beings (including us) he is dependent on God for his very existence, and is limited in space and time. Such power as He has can be overturned by God in a finger-snap. Christians have absolutely nothing to worry about from this enemy of God. As 1 John 4:4 says: "Greater is He Who is in you" (i.e., God) "than he who is in the world" (i.e., Satan).