First, some helpful background for you. The original book of II Peter in the Bible was written in Greek. The original book of Isaiah in the Bible was written in Hebrew. Catholic Jerome’s translation of the Hebrew book of Isaiah into Latin was only a translation.
Jerome, the Catholic Roman, is the first person to have coined the term “Lucifer” in the Bible. Jerome also had a fellow theological friend named Lucifer of Cagliari who fought side-by-side with him against Arianism. His friend’s followers were called Luciferians. The only time that “Lucifer” is used in the Bible is in Isaiah 14.
“Lucifer” is actually a Latin word that means “morning star; light-bearing” and is used in Isaiah 14 in later English translations for the person in Isaiah 14 who has fallen from heaven. Most theologians for centuries have agreed this person in Isaiah 14 is Satan. I tend to agree. The actual title used for this person, in the beginning of the passage, is the king of Babylon, but using the rules of interpretation which include usage, precedent, inference, context, historical meaning, and cross-references, it is fairly clear that this passage is speaking of Satan as being the person behind the king of Babylon’s power or perhaps even possessing the king of Babylon.
Has the Bible ever shown Satan or demons to be behind earthly thrones? Precedence exists in writings like that of the Book of Daniel where the demon known as “Prince of Persia” appeared to be the force behind the throne of Persia. Another example is that of Ezekiel 28. The list of other examples, precedents, and proof for this evil person being Satan are enormous. Thus, this is why most theologians for centuries agree this is Satan in Isaiah 14.
The Greek word “Phosphorus” means “morning star; light-bearing“. “Phosphorus” is a title used for Jesus Christ in II Peter 1:19. This means that “Lucifer” (a title for Satan in Isaiah 14) and “Phosphorus” (a title for Jesus in II Peter 1) both mean “morning star; light-bearing“. The Greek meaning of the Greek name “phosphorus” used for Jesus Christ in 2 Peter 1:19 can be seen at this link.
What’s the answer to this little mystery?
Jerome’s choice of the word “Lucifer” in Isaiah 14 is not the best translation, in my opinion, and is confusing at best, because the actual Hebrew word being rendered “Lucifer” in Isaiah 14 is the Hebrew word “Heylel” which is a form of “Halel” or “Hallel” (as in “Hallel-u-jah” which means “praise-you-Yahweh”). The word “Heylel” can mean “to praise” or it can also mean “to brag” or “to shine”. All of these meanings for “Hallel”, which is the actual Hebrew word in Isaiah 14, point to the “Heylel” or “the shining” as a shining of “glory” rather than a shining of “light”. Read the Hebrew definition at this link. You can also read the definition of “Lucifer” at this link. On the other hand, Paul the apostle says that Satan can transform into an angel of light. However, this does not allow us to translate the word “Heylel” (which is primarily boasting or praising) into “morning star” or “light-bearing”. Undoubtedly, this is not an easy translation.
Jerome was a man of Rome, and was a product of the newly formed Roman Catholic system that Constantine had borne by wedding together Baal sun worship with Bible beliefs. Jerome’s Latin Vulgate translation is undoubtedly a reflection of that mentality. Why are we surprised that a Roman Catholic would use confusing words that overlap the characteristics of Jesus and Satan? After all, the very belief system of Roman Catholicism has wed together the belief system of Satan (Babylonian Baal worship) and the belief system of GOD (Bible belief), has it not?
Babylonian Baal worship is virtually the mother of all religions, except Biblical belief, and Satan is behind this false system of Babylonian Baal belief, which after the scattering of people at the Tower of Babel and the confusion of languages, became a plethora of religions and a pantheon of gods. More on this subject can be read in this article (as well as this article and this article and this article and this article). The Roman empire has become the most recent, most powerful and longest enduring Empire-Religion to have incorporated Baal beliefs on a massive scale throughout her canons and dogmas. Ironically, Daniel 9 states that the “prince” or false christ who comes in the future would be of the people who destroyed the Jewish temple. We know from history who those people were – the Romans who destroyed the Jewish temple in A.D. 70.
Once we see the background of the translator who coined the term “Lucifer” (a term similar to Christ’s description of “phosphorus” in II Peter 1) in describing Satan, I believe we must reconsider his choice of words for translating the Hebrew word “Heylel“, especially knowing that “Heylel” was inspired by GOD, but the term “Lucifer” was not. A better rendering of this passage in my estimate, especially in the context of Isaiah 14 (which is Satan bragging on himself), is to call Satan by the name of “Shining (in the sense of glory or boasting), son of the dawn” rather than “Lucifer (morning star; lightbearing)”. Others may disagree.