Today the word 'Lucifer' is probably negative sounding in our ears, but it was not always so.  Its current, prevalent meaning in the Christian world originates mainly from a prophetic reference in the Old Testament.

1.  The etymology of the word

The name 'Eosforos' or ‘Lucifer’, is a composite word, and it means: 'The one bringing/ carrying the Dawn, or the first light” (of Creation)

Venus is closer to the Sun than the Earth, circling along an inner orbit, compared to the Earth’s. This, together with the fact that Venus is the planet closest to us, makes it appear brighter than other stars - not only because it reflects more sunlight than the outer and more distant planets, but also because it is larger than Mercury, and much further away from the Sun, (being between Mercury and Earth). Thus, while the Sun’s brightness outshines Mercury’s glow albeit very close to it, it does not do the same to Venus, but instead, it highlights it as the brightest planet for us on the earth's horizon.

Therefore, given that Venus is in an orbit closer to the Sun, it appears quite low on our own earthly horizon, either as the Sun sets, or before it rises.  Given that it appears just before the Sun rises or almost together with it at daybreak, it was considered 'the harbinger of dawn' – that is, 'the star that brings the dawn with it', or ‘Eosforos’ - the one who brings the dawn'.

For the same reason at the setting of the Sun – which it always accompanies at close range – the same planet is also called 'Esperos', or “Evening star” as it appears in the sky during the Evening, at sunset: when the day has finished (Es-peras)…

In the Old Testament, the word Eosforos retains the same meaning as the ancient Greek, as the star of the Dawn, which essentially represents the Dawn itself:

"…from eosforos to evening'. (1 Kings.30,17 ) = 'from the dawn of the coming day until the evening"

"…may he not see eosforos rising"  (Job 3,9) = "may he not see the day breaking"

"…from the womb I begat you, even before eosforos". (Psalm 109) = "I begat you even before the Morning Star".

5. Eosforos as a prophetic simile for the king of Babylon

In the Old Testament, in a prophecy by Isaiah about the king of Babylon, Eosforos appears personified as portraying that king.

In a Greek rendition of the Hebrew, the famous verse about Eosforos is included in Isaiah 14:3-21:

“3 And it shall be on that day that the Lord will deliver you (Israel) from your sorrow and your anger, and from your harsh slavery under which you had toiled for them. 4 And you shall take up this dirge for the king of Babylon, and you shall say on that day: [...]

...12 How has Eosforos fallen from heaven, who used to rise in the morning? He crashed upon the ground, he, who sent out (light) to all the nations! 13 For you (Eosforos) said in your mind: 'I will ascend to heaven, I will place my throne above the stars of the heavens, I will sit upon a high mountain – upon the high mountains that are towards the north; 14 I will ascend above the clouds; I will be just like the Most High.' 15 But now, you shall descend into Hades and the foundations of the earth. 16 Those who see you will wonder at you and they will say: ‘Is this the person who exacerbated the earth, who shook up kings? 17 He, who rendered the entire inhabited world a desert and destroyed his cities and did not release those in bondage. 18 All the kings of the nations were reposed with honour, and man in his own home; 19 but you will be cast away in the mountains like an abominable corpse, along with many other dead pierced by knives who descend into Hades. In the manner that a garment soaked in blood is unclean, 20 likewise you will not be clean, because you lost my land (Israel) and you killed my people; may you not remain in eternal time, o wicked spawn. 21  Prepare your children to be slaughtered for their father’s sins, lest they rise up and inherit the earth and fill the earth with wars.” 

Consequently, for the Jews the reference “How did Eosforos fall from heaven, who used to rise in the morning?” (Isa. 14:12 per the Septuagint), primarily refers with sarcasm here, to the fall of the king of Babylon, and not to the devil..

In this eschatological dimension, in addition to the Babylonian king, Eosforos is also reminiscent of the eschatological 'King of Babylon the Great' : the Antichrist.

We have pointed out in another article how Babylon also foreshadowed the eschatological political-religious capital of the Antichrist, and how the Antichrist, according to New Testament prophecies, will pronounce himself as 'god':

"And we ask you brothers, regarding the presence of our Lord Jesus Christ and our gathering together with Him... Let no-one of you be fooled in any manner, for, unless the apostasy comes first, then shall the man of iniquity, the son of perdition be revealed: the opposing one, who elevates himself above everyone and calls himself god or respect-worthy, who will seat himself in the temple of God displaying himself as a god.”    (2 Thessalonians 2:1,3-11).

According to these prophecies, the initially 'enlightened' leader, who will supposedly bring light to the peoples, will turn out to be a wretched ruler who will destroy his people (according to Zechariah), and will end up in Hades (according to Revelation)... exactly like Isaiah's Eosforos.

Finally, in harmony with Revelation’s link between the “therion” (beast) of the Antichrist and the Dragon-Satan (by describing both of them as beasts with 7 heads and 10 horns), likewise the Christian interpretation of Isaiah's prophecy about Eosforos sees in him – not only the Antichrist, but also Satan.

A correlation on this detail is based on the words of Christ Himself:  

“I saw Satan falling from heaven like a lightning bolt”.  (Isaiah 14:12 => Luke 10:18)

And in the same spirit, Revelation 12:8 says of the Devil:

“…and he did not prevail, nor was any place found for him in heaven. And so he was cast down: the dragon, the huge snake, the ancient one, the one called Devil and Satan, the deceiver of all the inhabited earth; he was cast down to earth, and his angels were also cast down who were with him.”

This last interpretation regarding the ambitious former 'bright angel' Satan who fell from his glory, is both the most familiar and the most prevalent one, to the point that the word Eosforos has come to mainly refer to Satan.

Beyond all the aforementioned, from time to time ecclesiastic Hymnography also uses similes for Her saints – for example the term 'eosfori' (=bearers of light - illuminators) for the bearers of the Light of God's Grace. An example is the following hymn pertaining to the Three Hierarchs:

“It is also fair to respect three Eosfori (Light-bearers) together, from within whose lives sprang forth the brilliant, three-fold Light...”.

Translation:  K.N.