“And the Word became flesh and dwelt among us, and we have seen his glory, glory as of the only Son from the Father, full of grace and truth.”
(John 1:14 ESV)
When John writes “the only Son from the Father,” the word “only” translates the Greek word μονογενουσ (monogenous), which the KJV translates “only begotten” and the ESV translates “only.” Neither translation gets at the heart of the word, not because the translators didn’t understand what they were doing, but because there just isn’t an English word that gets the Greek word “monogenous” exactly right. Monogenous means “being the only one of its kind or class, unique.” It’s a super important word because it’s the same word that John will use in John 3.16: “For God so loved the world,that he gave his only Son.” You can see that if we don’t understand the meaning of the word we are likely to go wrong, and by wrong I’m talking the “H” word (no, not hip-hop, although that would certainly be a metaphor for going astray in the music world), “H” as in heresy. What “monogenous” means exactly is the difference between historical Christianity and Arianism which was an open wound in the side of the church for centuries! (Yes. Centuries. I am not kidding).
Arianism is a heresy that said that Christ was not eternal, but was created by God before the creation of the world. In this belief Christ was made not begotten (although begotten isn’t a very good word either for that matter). Historical Christianity understood that when John says that Christ was God’s only Son, he did not mean that Christ was created or born or that there was a time in eternity past in which Christ did not exist; John means that Christ was the “one-of-a-kind” or “unique” Son of God (Ah, you are beginning to realize that perhaps theology might be important after all).
Some of the translations/paraphrases give us a flavor of what the word is getting at:
NLT – The unique one, who is himself God is near the Father’s heart
GNT – The only Son, who is close to the Father’s side
NRSV – It is God the only Son, who is close to the Father’s heart
The Message – This one-of-a-kind God-Expression, who exists at the very heart of the Father
In John’s writing “monogenous” is used only to describe Christ, so he wants to be sure that we understand the concept correctly.
So now we know what the word means, but what about the concept? What is John saying here? I think it all hinges on the word “glory” (doxan). We have seen the Word-became- flesh’s glory, glory as the only Son from the Father, full of grace and truth. Christ manifests or expresses or shines out God’s glory. The same glory that God the Father has, God the Son also has and reflects so that—as John will flat out state in another couple of verses—when we see Jesus, we see God. When we see Jesus’ glory, we see God’s glory.