The way, the truth, and the life – Jesus Christ, page-1945

"In other parts of the Bible, specifically in the Gospel of John, it is explicitly stated that "the Word became flesh"

Using the GREEKS correct word order, 1:14 says ZERO of a sort that "the word became flesh".

It simply says - And the word flesh (existing = Luke) became = on the scene.

YOU are trying to pull the cart before the horse, so to speak.
You are changing the truth of what "became" here.

Word Flesh or Word Man, IS describing someone existing who is going to do something = become, became on the scene and dwelt............
John is NOT describing the word/plan becoming flesh, the birth of Jesus, and John the Baptist confirms this in the next verse 15.

One only has to use the brains they were given -> You lot erroneously claim that most of the prologue is about Jesus, but you need to use the brain God gave you.

He came to his own and his own received him not = HOUSTON, how on earth could he come to his own, when he hasn't even become flesh Yet = DRRRRRRRRRRRRRRRRRRRRRRRRRRRRR!
To suggest the story flips back and forth, is a load of Hogwash = God is not a God of confusion.

And the Word (part of Expressed Luke) became Man -> Eph 3:9 (= The word, part of) And to make all men see what is the fellowship of the mystery, which from the beginning of the world hath been hid in God, who created all things. (Alone and by himself Isa 44:24)

You cannot deny the above, re Luke and maintain Bible truths, it simply cannot be done with truth.

And the word, another part expressed = become creation, John 1:3 smacks that truth, right in our faces, the plan/logos that was ongoing, in progress = toward the God and God (the subject now) was the Word and NOT Jesus.
While your word is in You, it is you.
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" hid in God," = the Only True God that Jesus references in John 17:3, it was not hid in Jesus or part of him.
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"where the eternal Word of God took on human form,"

It was the word of Life (plan) that was with the Father, NO pre-existing Jesus. 1 John 1:1,2 the scriptures which they handled, looked upon, heard from others etc, the scriptures Jesus referred to, that had life in them, and that life was to be through the Jesus to be, born from Mary.
Titus 1:2 (Word of Life with the Father) - In hope of eternal life, which God, that cannot lie, promised before time eternal;
2 Tim 1:9 - He has saved us and called us to a holy calling, not because of our works, but by His own purpose and by the grace He granted us in Christ Jesus (the one to be) before time eternal.

Not Jesus's purpose, but the God and Fathers, Yehowah's.
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"always God's intention for the Wword/plan Eph 3:9 to become flesh"

1:1b And the word/plan was (ongoing, in progress =) toward the God = Likes of Eph 3:9, Gens creation as shown to have been expressed in 1:3, coming FROM or derived from -> 1:1,2.
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" which has its roots in the Old Testament prophecies and promises."

And out of all these prophesies, NOT a single hint that the future one to come, was already existing in some form and would enter flesh or enter Mary, BECAUSE outside of the likes of Eph 3:9 as a plan, there was no pre-existing one.