Short answer: the texts do not give a definitive span - the “morning star” (often identified with Lucifer or a high-ranking angel) is portrayed as existing eternally with God before rebelling, so Scripture and early tradition describe no measurable earthly duration before his fall. The phrase “morning star” appears in few biblical passages and later Christian tradition. In Isaiah 14:12 the Hebrew word heylel (translated “morning star,” “day-star,” or “shining one”) addresses a proud ruler of Babylon in a poetic taunt; Latin translators and later Christian interpreters linked that image to a celestial being called Lucifer. Ezekiel 28:12–19 contains parallel language about a king of Tyre with exalted status “in Eden” and perfection “from the day you were created,” which some read as describing an angelic being’s uplift and subsequent pride. New Testament passages (2 Peter 1:19; Revelation 22:16) use “morning star” imagery positively for Christ, and Revelation 12 recounts a war in heaven in which a dragon expels a celestial figure and his angels - the most developed biblical account of an angelic fall. None of these texts gives a clockable interval during which that angel “walked the earth” before falling. The Isaiah and Ezekiel passages are poetic, addressing human kings through mythic language rather than offering a historical timeline. Revelation’s heavenly conflict is apocalyptic imagery, not a dated historical report. Early Christian writers (for example, Tertullian, Augustine, and later medieval theologians) developed the idea that certain angels fell because of pride, often identifying one as the chief rebel; but they describe angelic existence as fundamentally outside human chronology - angels are created beings with an origin but not a lifespan measured in earthly years before rebellion. Traditions that place fallen angels on earth for specified periods (for instance, some extra-biblical Jewish and Christian writings that describe angels marrying human women or blurring boundaries) vary widely in detail and are not canonical for most denominations. In short, canonical Scripture and mainstream theological tradition do not provide a factual length of time that the “morning star” spent on earth before falling. Attempts to assign a number rely on non-canonical stories, allegorical readings, or later theological speculation rather than on explicit biblical chronology.
