Many ppl think Lucifer was Satan pre-casting out of heaven. I don't think the context bears that fruit however. I will start with verse 5 of Isaiah 14... The Lord has broken the rod of the wicked, the scepter of the rulers, which in anger struck down peoples with unceasing blows, and in fury subdued nations with relentless aggression. All the lands are at rest and at peace; they break into singing. Even the junipers and the cedars of Lebanon gloat over you and say, “Now that you have been laid low, no one comes to cut us down.[vss 5-8] These verses appear to be speaking about actual rulers, as it uses plural pronouns to explain what the context is, and whom it addresses. The realm of the dead below is all astir to meet you at your coming; it rouses the spirits of the departed to greet you—all those who were leaders in the world; it makes them rise from their thrones—all those who were kings over the nations. They will all respond, they will say to you, “You also have become weak, as we are; you have become like us.” All your pomp has been brought down to the grave, along with the noise of your harps; maggots are spread out beneath you and worms cover you.[vss 9-11] Again, the context appears to be addressing ppl and not Satan. Look at that which I bolded. That is descriptive of a physical body after burial. How you have fallen from heaven, morning star, son of the dawn! You have been cast down to the earth, you who once laid low the nations! You said in your heart, “I will ascend to the heavens; I will raise my throne above the stars of God; I will sit enthroned on the mount of assembly, on the utmost heights of Mount Zaphon. I will ascend above the tops of the clouds; I will make myself like the Most High.” But you are brought down to the realm of the dead, to the depths of the pit. Those who see you stare at you, they ponder your fate: “Is this the man who shook the earth and made kingdoms tremble, the man who made the world a wilderness, who overthrew its cities and would not let his captives go home?”[vss 12-17] If you notice, the NIV does not use the word 'Lucifer' as other translations do. The context leading up to the passage was addressing actual ppl and not Satan, in my opinion. This is a picture of king Nebchadnezzer after he lost his mind and ate grass. In my opinion of course.