"Few English readers realise the fact that it is the king of Babylon, and not the devil, who is addressed as Lucifer. While this has been the history of the Latin word, its Greek and English equivalents have risen to a higher place, and the “morning star” has become a name of the Christ (
Revelation 22:16). "
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12. O Lucifer; son of the morning] In his splendour he is likened to the morning star; which was worshipped by the Babylonians under the name of Istar, and is described in Assyrian by an epithet, mustilil (shining star), which seems to correspond to the word here used (Schrader, Cuneiform Inscriptions, on this verse). The translation “Lucifer” (light-bearer) is quite correct, and is needlessly abandoned by the R.V. By some of the fathers the passage was applied to the fall of Satan (cf. Luke 10:18); hence the current use of Lucifer as a name of the devil.
For weaken, read lay prostrate.
12–15. The third strophe contains the prophet’s reflection on the sudden fall of the king of Babylon. That he should go to Sheol at all was a fate never contemplated by his soaring and self-deifying pride."
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(Note: It is singular, however, that among the Semitic nations the morning star is not personified as a male (Heōsphoros or Phōsphoros), but as a female (Astarte, see at
Isaiah 17:8), and that it is called Nâghâh, Ashtoreth, Zuhara, but never by a name derived from hâlal; whilst the moon is regarded as a male deity (Sin), and in Arabic hilâl signifies the new moon, which might be called ben- shacar (son of the dawn), from the fact that, from the time when it passes out of the invisibility of its first phase, it is seen at sunrise, and is as it were born out of the dawn.)
Lucifer, as a name given to the devil, was derived from this passage, which the fathers (and lately Stier) interpreted, without any warrant whatever, as relating to the apostasy and punishment of the angelic leaders. The appellation is a perfectly appropriate one for the king of Babel, on account of the early date of the Babylonian culture, which reached back as far as the grey twilight of primeval times, and also because of its predominant astrological character. The additional epithet chōlēsh ‛al-gōyim is founded upon the idea of the influxus siderum:
(Note: In a similar manner, the sun-god (San) is called the "conqueror of the king's enemies," "breaker of opposition," etc., on the early Babylonian monuments (see G. Rawlinson, The Five Great Monarchies, i.160).)
cholesh signifies "overthrowing" or laying down (
Exodus 17:13), and with ‛al, "bringing defeat upon;" whilst the Talmud (b. Sabbath 149b) uses it in the sense of projiciens sortem, and thus throws light upon the cholesh ( equals purah, lot) of the Mishnah. A retrospective glance is now cast at the self-deification of the king of Babylon, in which he was the antitype of the devil and the type of antichrist (
Daniel 11:36;
2 Thessalonians 2:4), and which had met with its reward."
https://biblehub.com/commentaries/isaiah/14-12.htm