The Monogenes Controversy: “Only” Or “Only Begotten”?
(See chapter 14, “God in Three Persons: The Trinity,” especially C.2.a, “The Arian Controversy,” on pages 243–45. See also the Nicene Creed on page 1169.)
The controversy over the term “only begotten” was unnecessary because it was based on a misunderstanding of the meaning of the Greek word μονογενής (from μονογενής, G3666, used of Jesus in John 1:14, 18; 3:16, 18; and 1 John 4:9). For many years it was thought to be derived from two Greek terms, μόνος (G3668), meaning “only,” and γεννάω (G1164), meaning “beget,” or “bear.” Even the received version of the Nicene Creed understands it that way, since the explanatory phrases “begotten of the Father before all worlds” and “begotten, not made” both use the verb γεννάω (beget) to explain μονογενής. But linguistic study in the twentieth century has shown that the second half of the word is not closely related to the verb γεννάω (beget, bear), but rather to the term γένος (G1169, class, kind). Thus the word means rather the “one-of-a-kind” Son or the “unique” Son. (See BAGD, p. 527; D. Moody, “The Translation of John 3:16 in the Revised Standard Version,” JBL 72 [1953], 213–219.) The idea of “only-begotten” in Greek would have been not μονογενής but μονογέννητος. However, it is not impossible that the Nicene fathers in 325 and 381 a.d. would have understood μονογενής to include the idea of “begetting,” since the word is used several times elsewhere to refer to someone who is an “only” child, and the idea of begetting could commonly be assumed to be present.
The fact that the word does not mean “the only son that someone has begotten” can be confirmed by noticing its use in Hebrews 11:17, where Isaac is called Abraham’s μονογενής (from μονογενής, G3666)—but certainly Isaac was not the only son Abraham had begotten, for he had also begotten Ishmael. The term there means rather that Isaac was Abraham’s “unique” son, that there was none other like him. (The word elsewhere means “unique” with no idea of begetting in view, in the LXX in Psalms 21:20 (22:20); 34:17 (35:17); Wisdom 7:22; 1 Clement 25:2.) Thus, the NIV translates John 3:16, “he gave his one and only Son,” and the NASB margin reads “or, unique, only one of His kind.” The RSV translates, “he gave his only Son.” All of these versions have rightly omitted any idea of “begetting” from the translation.
It is reassuring, however, to see that even though the early church had a misunderstanding of one biblical word, the rest of Scripture came to the defense of doctrinal purity and prevented the church from falling into the error of Arianism (although the struggle consumed most of the fourth century a.d.).
If the phrases “begotten of the Father before all worlds” and “begotten, not made” were not in the Nicene Creed, the phrase would only be of historical interest to us now, and there would be no need to talk of any doctrine of the “eternal begetting of the Son.” But since the phrase remains in a creed that is still commonly used, we perpetuate the unfortunate necessity of having to explain to every new generation of Christians that “begotten of the Father” has nothing to do with any other English sense of the word beget. It would seem more helpful if the language of “eternal begetting of the Son” (also called the “eternal generation of the Son”) were not retained in any modern theological formulations. Similarly, to refer to Jesus as God’s “only begotten” Son—language that derives from the King James translation—seems to be more confusing than helpful. What is needed is simply that we insist on eternal personal differences in the relationship between Father, Son, and Holy Spirit, and that the Son eternally relates to the Father as a son does to his father.
(The fact that Jesus is said to be “born of God” in 1 John 5:18 is probably not a reference to an eternal relationship, but rather refers to the incarnation when Christ was born as a man; compare Acts 13:33; Hebrews 1:5.)
Finally, in previous discussions of what this “eternal begetting” might have meant, it has been suggested that the Father has eternally been in some sense the source of the distinctions in role among the Father, Son, and Holy Spirit (e.g., Louis Berkhof, Systematic Theology, pp. 93–94). So long as we do not assume that these personal distinctions had a beginning at some point in time, nothing in Scripture would seem to contradict this idea, but nothing in Scripture would indicate that we should affirm it, either. Perhaps there is no meaningful sense in which we should speak about any one of the persons being a “source” of these personal distinctions, for they have always existed and are essential to the nature of God himself.[1]
[1] Grudem, W. A. (2004). Systematic theology: an introduction to biblical doctrine (pp. 1233–1235). Leicester, England; Grand Rapids, MI: Inter-Varsity Press; Zondervan Pub. House.