The focal point of generation is sameness, “after its kind.” The idea reveals sameness of essence. Some folks have gotten hung up on thinking that every moment by moment God is generating Jesus. This is not the focus at all, since this is an eternal relationship which can never change. It’s almost the same as saying that Jesus, moment by moment, is holding the universe together based upon Col. 1.17 stating as much. Rather, the bible is telling us things about God. God established relationships with His people and He wants us to know about Himself and His Son and that there is no other God. Additionally, the phrase is metaphorical. There is no similarity with human reproduction.
The edition of Bauer’s Greek-English Lexicon of The New Testament, and other early Christian literature that I have, doesn’t list a Greek word for “alone” or “unique.” This is because the N.T. and other Christian writers didn’t have the need for this term. Of course Jesus was unique in a special way but it wasn’t expressed since other concerns were much more in the forefront. The fulfillment of O.T. types and the need for identity with humans was what was stressed in Christian literature. There was a term in common circulation in the Greek 1st century which denoted “unique” or “alone” which was monērēs; this term, however, is not found in the N.T.
Monogēnēs is the underlying Greek term denoting “only begotten.” It is the word used in the bible to describe Jesus’ relationship with the Father. The meaning of the term can be deduced from how it is used in the text. Monogēnēs is found in Jn. 1.14 in connection with what precedes. Jn.1.13 speaks about being born (generation). It lists 3 ways natural children are conceived: blood (probably-human descent), of decision, and of the husband’s will. None of these examples is true for ‘one’ born (egennēthēsan) of God. This term is speaking about regeneration since God regenerates many individuals as His children. Back to the point about monogēnēs use in v. 14, here it speaks of a single generation from the Father of the Son. However, this is not a temporal relationship. What I mean is that the relationship is eternal; it always has been and is. This is the primary meaning of “I am” (ego eimi), the term Jesus used so creatively to say, “I am the Good Shepherd” and “I am the resurrection and the life.” What Jesus was saying, I believe, is that He is forever and always existing.
Some commentators looking at the term want to render monogēnēs: “one of a kind” or “unique” but this is not correct for at least 2 reasons. First, while it may be easier to dispense with difficult concepts which challenge comprehension, I believe the bible tells humans many things about God. God brings Christians in relationship with Him as children, and therefore He will teach them things about Himself. While God does not disclose everything to us, He tells us many things: I no longer call you servants, because a servant does not know his master’s business. Instead, I have called you friends, for everything that I learned from my Father I have made known to you. (Jn.15.15) NIV.
For instance, in Jn. 15.26, Jesus lets us know that the Spirit proceeds (ekporuetai) from the Father. I take this action of the Spirit as different and separate from the singular generation of the Son. A “son” is different from a “spirit,” in concept, and therefore requires a different operation of the Father in the act of proceeding. The Son was meant to be displayed while the Spirit is unseen and works internally in believers. The Son is eternally generated and the Spirit eternally proceeds from the Father.
Second, the reason why monogēnēs should not be translated as “unique” for Jesus, is that the early Greek-speaking Christians understood the term better than [what amounts to second guessing by] today’s non-native users of the language. The Nicene and Constantinople Creeds use the term to show the sameness of essence or substance (ousia). Whereas, uniqueness is inherent in “only born,” “only born” says more than just “unique.” The problem is that if monogēnēs is rendered “unique,” it doesn’t tell us enough.
Monērēs means “unique” or “alone” and did not enter N.T. usage, since the concept wasn’t required to describe anything by its writers. If John really wanted to stress the aspect that Jesus was unique, he could have used this term, which means exactly “one of a kind.” Yes, Jesus is unique by being singly generated by the Father, but this uniqueness is not the focus in the N.T.