I guess I have no idea why my posts were removed on another thread in this forum nor how this forum works . . . so here goes:
The word Lucifer is found in only one place in the Bible -- Isaiah 14:12 -- but only in the King James and related versions: "How art thou fallen from heaven, O Lucifer, son of the morning! . . ."
The New Revised Standard Version translates the same passage as "How you are fallen from heaven, O Day Star, Son of Dawn!"
In other translations we find: "O shining star of the dawn!" (Moffatt) or "O morning-star, son of the dawn!" (Hebrew Bible).
The King James Version is based on the Vulgate, the Latin translation of Jerome. Jerome translated the Hebrew helel (bright or brilliant one) as "lucifer," which was a reasonable Latin equivalent. And yet it is this lucifer, the bright one or lightbearer, that came to be understood by so many as the name for Satan, Lord of Darkness.
Lucifer is not an Adversary as the word Satan (Shaiten) describes
Lucifer is the 'Bringer of Light' in other words Lux Lucis (Lucifer) is gnosis, truth and Divine knowledge.
Lucifer makes His debut in the Testaments as the Serpent in the Garden of Eden pointing out to Eve that God is a liar and you will not die if you eat of the fruit of knowledge, which she did and did not die.
The term Lucifer in fourth century Latin was a name for Venus, especially as the morning star. The Latin word Lucifer is composed of two words: lux, or in the genitive form used lucis, (meaning "light") and ferre, which means "to bear" or "to bring." So, the word Lucifer means bearer of light or light bringer. The same word is used in other places in the Latin Vulgate to translate Hebrew terms that mean "bright," especially associated with the sky:
Babylonian religion was an astral religion, closely related to Canaanite practices, although more focused on the sun, moon, and stars and their motion than on the immediate cycles of nature as it was in Canaan. The Babylonians worshiped as gods the manifestations of celestial bodies. It is from Babylon that we get the signs of the Zodiac representing the constellations. We now know that the two terms used in the Hebrew text of Isaiah, Helel, morning star, and Shahar, dawn, were Babylonian astral deities (which is reflected in most modern translations).
Satan is a personification of the Judaic word al-satan or ha-satan (who borrowed it from the Persians' Shaiten) meaning adversary. The word is used more as a descriptive noun or pronoun. A fallen tree preventing a husband from getting to his injured wife would be considered a tree of shaiten, more or less.
Shaiten did not become Satan until much later where Jewish sects / tribes particularly the Essenes who began referring to anyone not an Essene as the Shaiten. Still further on the Roman Christian church decided it was time to personify Shaiten into Satan and have Him become the scapegoat for all evil in the Christian world.
All in all both Lucifer & Satan are metaphors that became archetypes and eventually personified, there are no Lucifer or Satan beings.
Whether they are constructs / thoughtforms of your mind is another story