When our church fathers defended one of the most important creeds (the most important creed, some might argue) in the history of the church—the Nicene Creed—they believed the biblical and orthodox doctrine of the Trinity hung in the balance, and with it, the survival of the church.

The Same God Who Works All Things: Inseparable Operations in Trinitarian Theology

Adonis Vidu (Author)

Wm. B. Eerdmans

368 pages

As they muscled their defense into place, they pinpointed several key beliefs as absolutely essential in the fight against heresy. One of these was “inseparable operations,” a belief summed up in a famous Latin phrase, opera Trinitatis ad extra indivisa sunt. What this means is that the work of the Trinity—from Creation to salvation—is undivided. Or as Augustine said with such elegance in his classic, De Trinitate, “As the Father and Son and Holy Spirit are inseparable, so do they work inseparably.” The Father, Son, and Spirit work as one because they are one—one in essence, will, power, and glory.

Enter modernity. The doctrine of inseparable operations—a “rule” once indispensable to Christian orthodoxy and liturgy—has been thrown into question: dispensed by some, severely modified by others. As theologian Adonis Vidu explains in his sobering new book, The Same God Who Works All Things: Inseparable Operations in Trinitarian Theology, “During the past century the rule has gone from being part of the very foundation of Trinitarian dogma to being dodged as one of its greatest vulnerabilities.”

What happened? And why does it matter?

A departure from Nicene tradition

The classical, Nicene tradition labored to preserve Scripture’s witness to the unity of the persons of the Trinity, and likewise their equality. This tradition distinguished the persons according to their eternal relations of origin: The Son is eternally begotten from the Father, who is himself unbegotten, and the Spirit eternally proceeds (or is “spirited”) from the Father and the Son.

Yet these “processions” (or personal properties) do not create three gods since, as the English Puritan John Owen said, “a divine person is nothing but the divine essence, upon the account of an especial property, subsisting in an especial manner.” For example, the church fathers not only said the Son is eternally begotten from the Father (this alone distinguishes the Son as Son); they were sure to clarify that the Son is begotten from the Father’s essence. As the early Christian apologist John of Damascus put it, the Trinity is “not one compound perfect nature made up of three imperfect elements, but one simple essence … existing in three perfect subsistences.” That word “simple” (or simplicity) is critical, guarding the church from turning the Trinity into a collection of separate parts—individuals who can be greater or lesser, superior or inferior.

Everything changed in the 20th century when theologians, departing from the Nicene tradition, began defining the Trinity as a society of separate agents, a society not unlike our human society. In a shocking statement, theologian Colin Gunton explained the new thinking like this: “What it is to be a human person is in this case identical with what it is to be a divine person, and therefore the word means the same at the levels of creator and creation.”

With the rise of what came to be called social trinitarianism, explains Vidu, the divine persons were redefined, as if each person were his own center of consciousness and will, his own distinct individual self. Christian philosopher Richard Swinburne has even proposed a Trinity composed of three individuals. Vidu’s research is revealing: If modern theologians still reserved a place for inseparable operations, they either described the unity of the Trinity in creation and salvation merely as a cooperative enterprise or as a division of labor. But in some cases, the doctrine was discarded altogether because it could not jibe with social trinitarianism’s emphasis on the individuality of the persons.

None of this sits well with Vidu. And as I see it, his theological angst is more than justified. Vidu is onto something when he concludes that modern theology has not only misconstrued but misused this core belief in inseparable operations. He writes, “It does not indicate that within the immanent life of the Trinity there are three separate agents who each have a separate will, a separate knowledge, and a separate love for the others”—as modern theologians assume. “Rather, it indicates that within the essential divine causality there obtain real and irreducible distinctions, that there are subsistent relations that distinguish and define the persons over against each other yet never against the substance.”

That last phrase—“yet never against the substance”—should not be overlooked. What is Vidu suggesting? By treating Father, Son, and Spirit as separate agents with separate wills, and explaining their unity of action as a matter of cooperative enterprise, we have set the persons over against their shared divine substance. Is it any wonder, then, why the charge of tritheism (three gods) has been leveled in recent decades?

Vidu also warns how easy it is to transition from a social definition of the three persons to relationships of supremacy and subordination between them. The Nicene creed unambiguously rejected the idea of the Son being subordinate to the Father—describing Jesus, for instance, as “true God from true God,” begotten “of the same essence as the Father.” But over the past several decades, many major evangelicals have created a new subordinationism, as if the Father has a superior authority and glory to the Son.

This is a sobering reminder that we have been more influenced by modern theology than we think. As clever as it sounds to say that the Son is ontologically equal with the Father but functionally subordinate, we must be discerning enough to see through such a false dichotomy. As Vidu helpfully observes, “A divine person is not one thing and the divine substance another. Rather each divine person is identical with the substance, but under a particular and irreducible relational aspect.”

If Vidu is right, then inseparable operations might just have a future in evangelical theology. But only if we first recognize that there are no individual actions, only Father, Son, and Spirit performing one single action.

Unity of action

The burden of Vidu’s book is to recover the doctrine of inseparable operations and with it the unity of the Trinity, a project long overdue. Vidu’s contribution shines brightest when he puts forward several test cases, including the Incarnation. Is the Incarnation the Son gone solo? Unfortunately, too many modern and evangelical theologians talk this way, as if exclusive actions can be attributed to individual persons.

Vidu enlists Augustine to admonish us: “The Trinity produced the flesh of Christ, but the only one of them it belongs to is Christ.” On the one hand, if inseparable operations is true, then the whole Trinity produces the “action” we call the miracle of the Incarnation. On the other hand, the “state” of the Incarnation—assuming human nature itself—belongs only to the Son.

That is not a contradiction. The singularity of the Trinity’s action stems from the singularity of the shared, common divine essence. And yet, the Son alone takes on flesh because each person may “appropriate” a work of salvation in a way that corresponds to that person’s eternal relation of origin. Since the Son is eternally begotten from the Father, it is fitting for the Father to send the Son to assume a human nature to his person and for our salvation. Or, as Vidu says with such precision, “the persons do not have their distinct actions, but they possess a distinct mode of action within the unity of the same action.”

Therefore, as Vidu argues, while we may look at a particular “created effect”—from Creation to Incarnation—and say that it “terminates” on a particular person, we should also recognize that any action is the one action of the whole Trinity. Vidu returns to an illustration throughout his book to capture this mystery: “Much like the metal object, which is moved by the whole magnet yet attaches distinctly to one of the poles, the human nature of Jesus Christ, the created effect of the mission of the Son, is produced by the whole Trinity yet attached to the Son exclusively.”

This illustration takes on flesh when the book arrives at Calvary. Vidu identifies with penal substitutionary atonement, the belief that on the cross Christ took our place and bore the penalty (divine judgment, eternal wrath) for our transgressions. However, he is quick to point out that some advocates have articulated this doctrine in a way that divides the Godhead. One recurring theory portrays the Father as the angry one in the Trinity, with the Son cast as the loving one. Another speculates that the Cross creates change in God, prodding him from holiness to love. Perhaps worst of all, some claim that, Jesus’ cry of dereliction—“why have you forsaken me?”—means the Trinity is divided at the cross, deity ruptured. Vidu’s recovery of inseparable operations is a needed correction: If penal substitution has any chance of escaping its own worst caricatures, it must avoid depictions that throw Nicene nuance to the wind in an effort to preserve divine satisfaction.

Nevertheless, one criticism should be raised. On the one hand, Vidu is as refreshing as he is honest, predicting the collateral damage should we fail to approach the Atonement within the guardrails of inseparable operations. On the other hand, I finished his atonement chapter still looking for exegetical guidance. If Christ’s cry of dereliction is not a split in the Godhead, how should Christ’s quotation from Psalm 22:1 be interpreted?

Vidu’s compelling theological case could be advanced further by attention to canonical categories. For example, Paul assumes in Romans 5 that Christ is the Second Adam. The first Adam represented his posterity, but his sin brought condemnation. Violating the covenant of creation gave birth to the curse of the cosmos. By contrast, the new Adam, Christ, represents the ungodly, but his fidelity to God’s law is our justification. In that light, the Cross is not a split in the Trinity, but the Son substituting himself and bearing the curse of Adam’s transgression, the law’s condemnation. Sounding a lot like the prophet Isaiah, the church father Gregory of Nazianzus wrote, “[Christ] was in his own person representing us. For we were the forsaken and despised before, but now, by the sufferings of him who could not suffer, we were taken up and saved. Similarly, he makes his own our folly and our transgressions.”

Vidu does not devote extensive attention to various biblical motifs. Nevertheless, by laying the philosophical foundation, he does leave open a window of opportunity. More work needs to be done locating these canonical themes within a Nicene framework, which is fruit still to blossom from the tree of theological interpretation.

Deep dogmatics

The Same God Who Works All Things is a superb example of deep dogmatics, the kind C. S. Lewis once said he enjoyed more than devotional books as long as he had a pencil in hand. Vidu is thorough and persuasive. Convicting—that may be the better word. His book leaves the reader lamenting our neglect and outright misuse of inseparable operations.

But if Vidu has his way, this will galvanize the church to join him in the recovery of Trinitarian orthodoxy. After a century of experimenting with the liberal project on a doctrine as consequential as the Trinity—and yes, I am speaking to evangelicals as complicit participants—the time is at hand to recover our orthodox heritage. And inseparable operations—as affirmed by the pro-Nicene tradition—is the right step to renewal.

Matthew Barrett is the author of Simply Trinity: The Unmanipulated Father, Son, and Spirit. He is associate professor of Christian theology at Midwestern Baptist Theological Seminary, executive editor of Credo Magazine, and host of the Credo Podcast.