True God from True God

One of the most essential doctrines for a Christian understanding of the Trinity is eternal generation. When the equality of the Son with the Father was thrown into question in the fourth century, the church fathers turned to the doctrine of eternal generation not only to distinguish the Son from the Father but to ensure that the Son is understood to be equal with the Father. For these reasons, the doctrine of eternal generation became a cornerstone of the Nicene Creed, that standard bearer of Christian orthodoxy. But over the last several decades, evangelicals have gained a bad reputation for rejecting this doctrine. Even when evangelicals have affirmed it, they do not appear to understand why. Could it be that we do not really grasp what eternal generation is in the first place?

I want to invite you on an adventure into the mystery of this indispensable Christian doctrine. But instead of exploring eternal generation’s biblical warrant (see Simply Trinity: The Unmanipulated Father, Son, and Spirit for that exciting journey), we will take the road less traveled and press into this doctrine’s theological reasoning.

Let the adventure begin.

What Is Eternal Generation?

The word generation means “coming forth,” and with reference to the Trinity it refers to the Son’s coming forth from the Father’s essence. The concept takes us to the very heart of what it means for the Son to be a Son. He is eternally from the Father, which is why He is called Son. To be more specific, from all eternity, the Father communicates the one, simple, undivided divine essence to the Son.

At the risk of stating the obvious, a son is, by definition, one who is generated by his father—one who has his origin from his father. While we will point out dissimilarities between human and divine sonship soon enough, we cannot miss the one fundamental similarity: sonship means one is generated by a father. When the concept is applied to the Son of God—as it so often is by the authors of Scripture—it means in its most basic sense that He, as the eternal Son, is from His Father.

To clarify, to be from the Father does not refer to the incarnation, to Christ as Mediator; being sent by the Father to save may reflect eternal generation, but it in no way constitutes eternal generation. Instead, to be from the Father refers to the Son’s origin in eternity, apart from creation. Generation is between Father and Son, an eternal act, and not between the Trinity and creation, as if it were a temporal act. As we will learn, generation is internal to the triune God—ad intra, as we like to say in Latin, as opposed to external, ad extra. The Father’s sending His Son into the world on mission for the world reflects the Son’s eternal origin from the Father (generation), but that mission in no way constitutes His eternal relation of origin. The Son is generated (begotten) by the Father before all ages apart from the world, irrespective of creation. He is Son whether or not He is ever sent into the world; He is the eternal Son from the Father whether or not He ever becomes incarnate. It is the immanent Trinity that is in view, not the economic.The Son is generated (begotten) by the Father before all ages apart from the world, irrespective of creation. Click To Tweet

There is another term that conveys the concept of generation: begotten. Perhaps you’ve heard the word used when reading those long genealogies in the Bible: so-and-so begat so-and-so begat so-and-so. But John applies this language to Jesus as well, referring to Him as the only begotten Son of God (e.g., John 1:14, 18; 3:16, 18). This begotten language, however, long predates the King James Bible. Way back in the fourth century, the church fathers who wrote the Nicene Creed used it as well. For example, the Nicene Creed says, “We believe in . . . one Lord Jesus Christ, the only-begotten Son of God, begotten from the Father before all time.”

This is the One, undivided God we are talking about; therefore, for the Son to be begotten from the Father means that God is begotten from God, which is why the creed confesses the Son to be “true God from true God.” To confess the Son as true God from true God is not an overstatement since He is, we dare not forget, consubstantial with the Father. Consubstantial means the Son is equal to the Father in every way, from the same essence or substance as the Father, no less divine than the Father. But we can only affirm such coequality if the Son is begotten from the Father’s essence. For if the Son is not begotten from the Father, the divine essence cannot subsist (exist) in the Son.

Furthermore, generation alone is what distinguishes the Son as Son. There is not some other concept or function or activity in the Trinity that distinguishes the person of the Son from the person of the Father. Generation alone can, for it alone conveys the nucleus of sonship. That is no small point, because without generation, not only is there no Son, but there is no Trinity. As the Calvinist Baptist John Gill warns, “Without his eternal generation no proof can be made of his being a distinct divine Person in the Godhead.”¹ Without generation, we fall headfirst into Sabellianism, for what previously distinguished Son from Father is dissolved, and as a result the persons are conflated until there is no plurality of persons at all.

When Is the Son Generated?

With the basic idea of generation in place, we must qualify Sonship in the Trinity lest we interpret it in a literalistic fashion, with a one-to-one correspondence to creaturely sonship. There are significant differences between a divine generation and a human one. Understanding these differences—what eternal generation is not—aids us in better understanding what eternal generation is. It also avoids legions of heresies. Let’s begin with this question: When is the Son generated by the Father?

That’s a trick question if there ever was one.There is no “when.” Why? The short answer: our triune God is eternal. He is not bound by time but is timeless; He has no beginning. A succession of moments cannot apply to Him. He just is. That means the following question is most relevant:

Q: If God is timelessly eternal, what does that mean for the Son and His generation from the Father?

A: Unlike human generation, the Son’s generation is eternal. There never was a time when the Son was not, nor ever a time when the Son was not from the Father.

Or, as early church fathers like Gregory of Nyssa like to say, there is no “sometime” for the Son because He was not generated in time. “He exists by generation indeed, but nevertheless He never begins to exist.”²

It’s not as if God the Son did not exist but then came into existence at a point in time, created by the Father and therefore after the Father. That may describe how generation works in our human existence, but it cannot depict the Son’s generation. He is, says Nicaea, “begotten not created.” He is, we cannot forget, the eternal Son from the Father. If the divine essence subsists in Him, then He too shares in the attributes of deity, eternity being one of them. He is no creature, and if not a creature, then His generation cannot be temporal. The generation of the Son, Gregory of Nyssa said, “does not fall within time, any more than the creation was before time.”³

If the Son’s generation did fall within time, then not only is there a time when the Son was not, but there is a time when the Father was not Father. And if there was a time when the Father was not, then there was a time when the Trinity was not. As Athanasius points out, “If the Son is not proper offspring of the Father’s essence, but of nothing has come to be, then of nothing the Triad consists, and once there was not a Triad, but a Monad.”⁴

Furthermore, if He is Son because He is from the Father, then His sonship must be as eternal as the Father Himself, at least if He is begotten from the same essence as the Father. That is why the Nicene Creed stresses that the Son is “begotten from the Father before all time . . . begotten not created . . . through Whom all things came into being.” The generation within God is unlike any other; it is not susceptible to the limitations of time. The Son’s filial identity has no duration or succession of moments; it is timeless. Everlasting in nature, there never was a time when the Son was not begotten from the Father.

That may sound like a contradiction—how can someone be generated and eternal? It sounds like a contradiction because we know generation only within the experience of our own finitude. For the infinite, timelessly eternal deity, the confines of our finitude do not apply. Let’s not forget that whatever words are used of God—even scriptural words and metaphors—this is God we have in view, infinite and eternal, immutable, and everlasting. Language is, by definition, analogical in every way. The metaphor must then be adapted to the incomprehensible One, not vice versa. So too with generation. As Augustine says, since the generation of the Son is eternal, “one exists not as before the other, but as from the other.”⁵ The Son is not generated after the Father, which would make Him less than the Father, but the Son is generated from the Father and from all eternity.

One more thing: Scripture refers to the Son’s eternal origin from the Father with a variety of metaphors, including Radiance, Image, Wisdom, Word, and Ancient of Days (each of which I treat at length in Simply Trinity). But one we can consider here is truth. As Jesus Himself says, He is the truth (John 14:6). Was there ever a time when God the Father was without His Truth? The Arians of the fourth century said yes. With a look of terror on his face, the church father Athanasius ponders this bizarre scenario: “For if the Son was not before His generation, Truth was not always in God.” It is a sin to say such a thing, Athanasius concludes. That sin multiplies if we also say there was a time when the Image was not, for “God’s Image is not delineated from without, but God Himself hath begotten it; in which seeing Himself, He has delight. . . . When then did the Father not see Himself in His own Image?”⁶

Answer: never.

The Father always and forever has seen Himself in His own image. So yes, the Son is the image of the Father, but unlike images in our finite world, there has never been a time when the Son was not the image of the invisible God (Col. 1:15).

Nine Marks of an Unhealthy Generation

As we have seen, the doctrine of eternal generation is a doctrine that takes us to the very heart of what it means for the Son to be a Son. From all eternity, the Father communicates the one, simple, undivided divine essence to the Son. We also stressed that divine, eternal generation must be distinguished from human, temporal generation. We must rid our minds of anything impure.

But what else might that include?

The Calvinist Baptist John Gill once listed nine marks of human generation that should not characterize divine generation. Actually, these are not original to Gill, but are voiced by the Great Tradition as well, as seen in men such as Gregory of Nyssa. These are the nine marks of an unhealthy generation:

1. Division of nature
2. Multiplication of essence
3. Priority and posteriority
4. Motion
5. Mutation
6. Alteration
7. Corruption
8. Diminution [i.e., to lessen]
9. Cessation from operation⁷

We cannot touch on every one of these. But we can address a few that are especially dangerous.

No Multiplication, No Division

The Son’s generation involves no multiplication or division of nature. No multiplication of the divine essence is involved in the generation of the Son. When the Father begets, He communicates the one (simple) divine essence to His Son, but He does not multiply the divine essence. If He did, there would no longer be one, simple essence but two essences. Likewise, when we say the Son is begotten, we do not mean He receives from the Father the divine essence in part but that He receives it in whole.

Or think of it this way: God is “not triple (triplex) but trinitary (trinum).”⁸ The Father does not give to His Son what He previously received from His own Father. Generation works that way among created, finite fathers, but God the Father has no beginning; nor is He Himself generated. He is fathered by no one. He alone is unbegotten, without origin. “Human parents transmit what they have received,” but “God the Father alone gives to the Son and to the Holy Spirit what He has from no other person.”⁹ This does not involve a multiplication of the divine nature, which would result in three gods (tritheism). The Son is begotten of the Father by nature, so that the Son is a subsistence of that one divine nature, not the production of another, second nature.

Not only is the divine nature not multiplied, but it is not divided as a result of the Son’s generation either. In the fourth century, the Arians claimed it must be divided. They appealed to divine simplicity to argue against the Son’s eternal generation from the Father and coequality with the Father. As Athanasius reports, the Arians “deny that the Son is the proper offspring of the Father’s essence, on the ground that this must imply parts and divisions.”¹⁰ The Son cannot be from the Father’s essence, for then the Father must part with a portion of the essence to generate a Son.

In human generation, the human nature is divisible. It can, Francis Turretin says, “remain the same in species when propagated by generation, although it is not the same in number because it detaches a certain part of its substance, which passes over to the begotten.”¹¹ That’s because human generation is physical and material. The divine nature, however, is spiritual and therefore indivisible. God is spirit, so He remains one, simple, and undivided. Thus, some call the generation of the Son hyperphysical to communicate that the Son’s generation is not in time or space; nor does it result in divisible parts.

As mentioned, the Son does not receive what the Father received from His father, since the Father has no father Himself. It does not follow, however, that the Son is born out of nothing (ex nihilo) as the Arians insisted. If He was, then He would be no different from the rest of creation, which was made by God out of nothing. But the Son is no creature; yes, He is begotten, but He is not made (Nicaea). Let’s not confuse the two. Rather than the Son being “born out of nothing,” Thomas Aquinas says, He is “born out of the substance of the Father.”¹²

Again, this should not be taken in the human sense. The “Son of God is born of the substance of the Father. Yet not in the same way as a human son. For a part of the substance of the human father passes into the substance of his offspring.” That would divide up the substance or nature of God. By contrast, the divine substance “is above being divisible.” The Father “in begetting the Son did not pass on part of his nature to the Son, but bestowed the whole nature upon him, with only the distinction based on origin remaining.”¹³ The divine nature belongs to the Son—not in part, but in whole—due to His origin from the Father, and if in whole then the divine nature has been neither multiplied nor divided.

Notice, divine simplicity plays a major factor at this point. Since God is not made up of parts, it’s not as if eternal generation involves a portion of the divine essence being broken off and given to the Son by the Father. The Son, Hilary of Poitiers objects, is no “mutilated fragment of the Father.”¹⁴ Not only would that make God a composition of parts, but it would sacrifice the full deity of the Son, as if He were only part divinity. Nor would the Trinity be simply Trinity. Rather, to be begotten from the Father is to wholly possess the one, undivided divine essence. “That birth, which brought Him into being, constituted Him divine, and His being reveals the consciousness of that divine nature. God the Son confesses God His Father, because He was born of Him; but also, because He was born, He inherits the whole nature of God.”¹⁵ Each person is a subsistence of the one divine nature, that nature wholly subsisting in Father, Son, and Holy Spirit. “The Son is begotten of (de) the Father’s essence,” Thomas Aquinas says, “because the Father’s essence, bestowed on the Son through generation, is subsisting in the Son.”¹⁶

Since the Son is begotten of the Father’s essence, there is “no partition, or withdrawing, or lessening, or efflux, or extension, or suffering of change, but the birth of living nature from living nature”; eternal generation is “One from One,” that is, “God going forth from God.”¹⁷ Or as the Nicene Creed says, the Son is “true God from true God.” The Son’s existence “did not take its beginning out of nothing, but went forth from the Eternal.” It is appropriate to still call it a birth (that is the meaning of begetting), but “it would be false to call it a beginning.”¹⁸ Birth, not beginning. Unlike the creation of the universe ex nihilo, the “proceeding forth of God from God is a thing entirely different from the coming into existence of a new substance.”¹⁹ Hilary is right: the Son “has no origin external to God, and was not created out of nothing, but is the Son, born from God.”²⁰

If the Son’s generation involves no multiplication or division, are we safe to conclude that it can involve no priority and mutation either?

No Priority, No Posteriority, No Inferiority

We have now been warned against nine marks of an unhealthy generation. But what else must be excluded from this divine generation? Don’t take that question lightly. A right answer might just guard you from heresy, especially considering the dangers that lie at the end of our adventure. Consider with me two final marks of an unhealthy generation.

The Son’s generation involves no priority or posteriority, and certainly no inferiority but designates order alone. If it did involve priority or posteriority of any kind, then the Son would be inferior to the Father.

Previously, I emphasized that the Son is begotten by the Father, but unlike our human experience, the Son’s generation is eternal (before all ages, timeless). And if eternal, then the generation of the Son is not the generation of a lesser being (made in time or before time) but the generation of a Son who is equal in deity to His Father. But the reason the Son is not inferior to the Father is because the one divine essence wholly subsists in the Son due to His generation from the Father’s nature or substance. As the Son is true God from true God, there can be “no diminution of the Begetter’s substance” in the generation of the Son.²¹ The Father begets His Son, and the two are, to return to that key word from Nicaea, consubstantial, meaning they are to be identified by the self-same divine essence. Priority or posteriority would undermine the Son as consubstantial, as One who is of the same nature as the Father.

As we’ve learned, the lack of priority or posteriority is due in part to the timeless nature of the Son’s generation, which is eternal, not temporal. Gregory of Nazianzus was once asked why the Son and the Spirit are not co-unoriginate along with the Father if it is true that they are coeternal with the Father. His response: “Because they [Son and Spirit] are from him [Father], though not after him. ‘Being unoriginate’ necessarily implies ‘being eternal,’ but ‘being eternal’ does not entail ‘being unoriginated,’ so long as the Father is referred to as origin.” To drive this point home, Gregory appealed to the illustration of the sun. “So because they [Son and Spirit] have a cause they are not unoriginated. But clearly a cause is not necessarily prior to its effect—the Sun is not prior to its light. Because time is not involved, they are to that extent unoriginated—even if you do scare simple souls with the bogey-word; for the sources of time are not subject to time.”²²

With a nudge from Gregory, consider the biblical imagery of light (John 1:4, 8–9). The Nicene Creed says the Son’s eternal generation from the Father can be compared to “light from light.” The Cappadocian Fathers (Basil the Great, Gregory of Nyssa, and Gregory of Nazianzus—key fourth-century church fathers who helped clarify our doctrine of the Trinity) also appealed to this imagery of light to counter the belief of subordinationists who said an effect is inferior to its cause, the Son subordinate to the Father. Consider the sun, they said in response. It is the cause of light, but by no means is light inferior to its source. In essence, they are one and the same. How much more so with divinity? Is not the divine essence simple and inseparable, eternal, and immutable?

We might also add that the Son cannot be less than His source (the Father), because there is no hierarchy in the Trinity. The Father is not greater than the Son—not in any way. In order to avoid misunderstanding, some may prefer the word source instead of cause (as I do) when talking about the Father, which better safeguards the Son’s equality. But regardless, in the Great Tradition neither word means the Son has a beginning or is less than the Father because He is from the Father.

In sum, the Father is the principle in the Godhead—the principle who alone is without principle. Unbegotten. But that does not mean that the Father and Son are not coequals. Rather, the eternal relations reveal the origins of the persons. To read hierarchy of any kind into these origins is to abuse them, even manipulate them. (This includes recent attempts to subordinate the Son to the Father within the immanent life of the Trinity.) The Father may be the principle without principle, but He is also the “principle without priority.”²³ Whenever we or the Great Tradition uses words such as source, the intention is only to identify the personal origin of the Son: the Father. Hierarchy and priority are precluded by the very nature, will, power, and glory the three persons hold in common. As Gregory of Nazianzus says: “They do not have degrees of being God or degrees of priority over against one another. They are not sundered in will or divided in power. You cannot find there any of the properties inherent in things divisible.” In short, “The Godhead exists undivided.”²⁴

If the Son’s generation from the Father involves no priority, can we also say it involves no mutation?

No Change

The Son’s generation from the Father involves no change in God. In a sermon series on the Gospel of John, Augustine once said to his congregation, “Although changeable things are made through the Word, that Word is unchangeable.”²⁵ God may create the changeable world through His Word, but remember, the Word Himself does not change. For He is not created but begotten from the Father’s nature from all eternity. The Son, Athanasius says, “being from the Father, and proper to His essence, is unchangeable and unalterable as the Father Himself.”²⁶ Whereas a bodily begetting involves mutation, a begetting that is without a body (incorporeal) does not.²⁷

Remember, says the seventh-century church father John of Damascus, eternal generation means that the Son is “from the Father’s nature.”²⁸ If He is from the Father’s nature, a nature that is not only simple and eternal but immutable (unchanging), then no change can occur in generation. If it does, then either the Father’s nature is not immutable or the Son is generated from another nature, external to the Father, and in that case could no longer be coequal to the Father in divinity.

In John Gill’s nine marks of an unhealthy generation, you may have noticed that five of them—motion, mutation, alteration, corruption, diminution—have one thing in common: they are all the result of change. This is inevitable with human generation, for where finite creatures are involved there is always change, and where there is change, we have the potential to change for the worse, which means corruption is a real possibility.

But not so with the triune God, whose nature is not only eternal but immutable. If immutable, then the Father begets His Son without alteration to the divine nature. That is because there is no potency in God, meaning God has no unactualized potential He must reach, as if He is not true God until He reaches His full potential. Instead, He is the perfect being, self-existent, self-sufficient, always and forever His perfect self, maximally alive, without any need to somehow become more perfect than He is for all eternity—which is why the fathers called Him pure act. The Father does not beget His Son as if the Son must somehow reach His potential over time, as if He must grow and change and become more perfect than He was before. Remember, the Trinity is perfect, maximally alive, never in need of becoming something more or greater or better. That means eternal generation “is a perfect generating perfect act.”²⁹ Perfect generating perfect—that sounds a lot like Nicaea’s true God from true God.

All that to say, if the Son’s generation is eternal, so also it must be immutable. Where there is a succession of moments (time), change will follow; indeed, it must. But in eternity, there is no successiveness and therefore no mutation in God. The Father begets His Son not as a new moment in time but from eternity. To say, as the Nicene fathers did over against the Arians, that there never was a time when the Son was not is to also confess there never was a time when the Son was not immutable. If He was not begotten out of the eternal, immutable nature of the Father, then we would be right to ask whether something is lacking in God, whether God Himself is incomplete and imperfect.

But we can rejoice with Thomas Aquinas, who says:

The Father’s nature has been complete from all eternity; the action whereby the Father brings forth the Son is not successive, because then the Son of God would have been begotten in stages and his begetting would have been material and involved movement. All impossible consequences. What remains, then, is that whenever the Father was, the Son also was and so is co-eternal with the Father, as also is the Holy Spirit with them both.³⁰

May the Adventure Continue

I’m afraid our adventure must end. But your adventure has only just begun. For the Trinity, after all, is a marvelous mystery, summoning many a Christian wayfarer to explore its infinity glory. Before I leave you, I’m afraid I must warn you. Along the way, you will meet some who dismiss this Christian doctrine called eternal generation. Others will join you on your journey, but as your pilgrimage continues, you will find they misuse, even manipulate this Christian doctrine for their own agenda. But if you remain faithful, you will reach the blessed land of the Trinity, and there your theology will turn into doxology.

*Editor’s note: This article is an excerpt from Matthew Barrett’s book, Simply Trinity: The Unmanipulated Father, Son, and Spirit, and is used with permission. This excerpt was also published on Tabletalk by Ligonier and is used with permission.

Notes:

1. John Gill, Body of Divinity, 144.
2. Gregory of Nyssa, Against Eunomius 1.39 (NPNF2 5:94).
3. Gregory of Nyssa, Against Eunomius 1.26 (NPNF2 5:71).
4. Athanasius, Against the Arians 1.6.17 (NPNF2 4:316).
5. Augustine, Contra Maximinum 2.14; cf. Thomas Aquinas, Summa Theologiae 1a.42.3, emphasis added.
6. Athanasius, Against the Arians 1.6.20 (NPNF2 4:318).
7. John Gill, Body of Divinity, 146.
8. John Forbes, Instructiones hist. 1.33.1, 3; quoted in Richard A. Muller, Post-Reformation Reformed Dogmatics (Grand Rapids, Mich.: Baker Academic, 2003), 4:170.
9. Gilles Emery, The Trinity: An Introduction to Catholic Doctrine on the Triune God (Washington, D.C.: Catholic University of America Press, 2011), 120.
10. Athanasius, Against the Arians 1.5.15 (NPNF2 4:315).
11. Francis Turretin, Institutes of Elenctic Theology, 1:256.
12. Thomas Aquinas, Summa Theologiae 1a.41.3.
13. Thomas Aquinas, Summa Theologiae 1a.41.3, emphasis added.
14. Hilary of Poitiers, On the Trinity 3.23 (NPNF2 9:69); cf. 4.4 (NPNF2 9:72).
15. Hilary of Poitiers, On the Trinity 11.12 (NPNF2 9:207), emphasis added.
16. Thomas Aquinas, Summa Theologiae 1a.41.3.
17. Hilary of Poitiers, On the Trinity 6.35 (NPNF2 9:111).
18. Hilary of Poitiers, On the Trinity 6.35 (NPNF2 9:111).
19. Hilary of Poitiers, On the Trinity 6.35 (NPNF2 9:111).
20. Hilary of Poitiers, On the Trinity 7.2 (NPNF2 9:118); cf. 9.30 (NPNF2 9:165). Also see Thomas Aquinas, Summa Theologiae 1a.41.3.
21. Hilary of Poitiers, On the Trinity 5.37 (NPNF2 9:96).
22. Gregory of Nazianzus, On God and Christ 3.29.3 (p. 71).
23. Scott R. Swain, “Divine Trinity,” in Christian Dogmatics: Reformed Theolgoy for the Church Catholic, eds. Michael Allen and Scott R. Swain (Grand Rapids, Mich.: Baker Academic), 99, emphasis added.
24. Gregory of Nazianzus, On God and Christ 4.31.14 (p. 127).
25. Augustine, Homilies on the Gospel of John 1–40, 1.12.
26. Athanasius, Against the Arians 1.10.36 (NPNF2 4:327).
27. Gregory of Nazianzus, On God and Christ 3.29.4 (p. 72).
28. John of Damascus, Exposition of the Orthodox Faith 8 (NPNF2 9:7).
29. Matthew Levering, Scripture and Metaphysics (Hoboken, N.J.: Wiley-Blackwell, 2004), 156.
30. Yet the “Father does not beget the Son by will, but by nature.” Thomas Aquinas, Summa Theologiae 1a.42.2.