Now, there is an issue of word rendering in Micah 5:2 as it relates to the divinity of Christ. Translations such as the English Standard Version render the Hebrew word "olam" in this text as from ancient days, while others such as the New American Standard and King James read as from eternity. The Hebrew can either refer to unending time or to some distant point in the past. It can be proved beyond a reasonable doubt that the Prophet Micah was conveying the meaning of eternity. The King being described in Micah 5:2 has supernatural qualities. The Aramaic Targum Jonathan translates the verse as follows (originally cited here):
“. . . out of thee shall proceed in my presence the Messiah to exercise sovereignty over Israel; whose name has been called from eternity, from the days of the everlasting.” (Ankerberg, Weldon, and Kaiser, The Case for Jesus the Messiah: Incredible Prophecies that Prove God Exists, p. 75-76)
The Lord Jesus Christ did not exist eternally as a human. He had a "beginning" as a man. God the Son took on human flesh. The phrase "ancient of days" refers to the incomprehensible essence of eternity. This source provides some relevant historical information:
"Eliezer makes a remarkable observation: though the Messiah will be born in Bethlehem, he existed “before the world was created” (Pirkei deRabbi Eliezer 3:1). Micah says his goings forth are מִימֵי עֹולָֽם mimei olam (“from the days of eternity”). In other words, the Messiah has eternally existed. The Messiah is not a created being. The text implies a divine nature. Early Jewish interpreters understood this. The writer of 1 Enoch says, “From the beginning the Son of Man was hidden and the Most High has preserved him” (1 Enoch 62:7). Classical rabbinic texts described a pre-existent Messiah in b. Pesachim 54a, Nedarim 39a, the Revelation of R Joshua b Levi, and Seder Gan Eden." (Jacobs and Buttenweiser, “Messiah,” 511)"
The text is obviously discussing the pre-existence of the Jewish Messiah. The idea of beginnings is emphasized twice in a row in the same passage (consider also the rendering of Micah 5:2 as found in the New International Version where it says "origins"), meaning that Jesus Christ is eternal. If this text of Scripture is referring to a specific point in time when the Messiah was created by God, then it would simply be meaningless and redundant. It would not make any sense for Him to be brought into existence many times. An excerpt from the Jamieson-Fausset-Brown commentary says the following:
"goings forth . . . from everlasting--The plain antithesis of this clause, to "come forth out of thee" (from Beth-lehem), shows that the eternal generation of the Son is meant. The terms convey the strongest assertion of infinite duration of which the Hebrew language is capable (compare Psalms 90:2 , Proverbs 8:22 Proverbs 8:23 , John 1:1 )."
The Reformation Study Bible has this note on Micah 5:2:
"from ancient days. This expression can also be translated “from days of eternity.” Indeed, “from of old” is rendered “from everlasting” in Hab. 1:12, where it is applied to God Himself (cf. “eternal God,” Deut. 33:27). Micah has certainly learned that the ruler’s origin long predates His anticipated future coming. A more-than-human figure is involved."
D.A. Carson and Gregory K. Beale provide these comments regarding Matthew paraphrasing the Messianic prophecy given through Micah (originally cited at Evidence Unseen):
“A literal translation of Mic. 5:1 MT (5:2 ET) reads, “And you Bethlehem Ephrathah, little [or, ‘insignificant’] among the thousands [or, ‘clans’] of Judah, from you to me will go forth to be a ruler in Israel.…” Micah 5:1 LXX (5:2 ET) translates the Hebrew quite literally, but adds “house of” before “Ephrathah” and changes “thousands” to “rulers of thousands.” Matthew follows the LXX verbatim for “and you Bethlehem,” replaces “(house of) Ephrathah” with “land of Judah,” adds “by no means” before “little,” changes the adjective to the superlative form “least,” replaces “rulers of thousands” with “governors,” omits “to me,” but then reproduces “out of you will go forth” using LXX wording.” (Beale, G. K., & Carson, D. A. (2007). Commentary on the New Testament use of the Old Testament (6). Grand Rapids, MI; Nottingham, UK: Baker Academic; Apollos)