The doctrine of the Trinity ultimately rests on the biblical datum of inseparable operations. But the reverse is also true: triune unity necessarily implies the inseparability of God’s external operations.

For both teachers and pastors, the doctrine of the Trinity has been one of the most demanding topics, often resulting in glazed-over student eyes, or in yawning parishioners thinking ahead to Sunday lunch or football. Needless to say, neglect of such a foundational doctrine, which has been called a “distributed doctrine”[1] because of how broadly its tentacles spread throughout the system of doctrine, will have cascading consequences. In recent years we have observed the retrieval of important aspects of trinitarian orthodoxy, including the doctrine of eternal generation, the ontological (and functional) equality of the divine persons, in some quarters the doctrine of the filioque, and an additional aspect which forms the focus of this article: inseparable operations.

Inseparable Operations and Contemporary Confusion

Simply defined, the doctrine of inseparable operations affirms that the triune persons act as a single agent externally, while internally their operations are divided.[2] Easy to say, harder to understand, even harder to teach and preach! Having taught this doctrine to graduate students, with particular emphasis during the last ten years, it is one of the most counter-intuitive doctrines they will have encountered in seminary. This is evidence for the domination of a functional tritheism in our churches, sometimes generated by a social understanding of the Trinity. By a functional tritheism I mean the belief that the different divine persons do their own thing, each having their own role, and each being responsible for certain effects. Most crudely, the Father alone is often thought to create, while only the Son redeems and only the Spirit sanctifies or perfects. Or, in what is one of the most damaging caricatures of all, the stern Father awaits in heaven for the Son to complete his mission, upon which he acts, restoring fellowship with sinners and sending the Holy Spirit. It gets worse when we begin to reflect on the cross itself: either the Father turns his eyes away from the Son, or the Father unilaterally acts to punish the Son, or the Father breaks relations with the Son, etc. These images populate our sermons, they have penetrated our hymnody, and they shape our collective consciousness.

And yet the Christian tradition has been consistently resisting such an understanding of the external operations of the triune persons. The distribution of such actions and roles among the persons indicates that they have separate substances, that is, that they are separate beings. No matter how closely such actions are coordinated, how symphonically they weave together, they remain the actions of distinct beings. Some have tried to jazz this up by speaking of a perichoretic dance of the persons, one that is not scripted, but which ultimately resolves into a greater and mysterious unity. Yet, even in the most intimate dance there are two dancers, two beings. The unity they make up is a composed unity, that is, a unity which presupposes the existence of the various parts. Not even the most raging heretics in the hey-day of heresy could entertain such a thought, all too common today. Why not? Because anything which is composed cannot be perfect. A composed being depends on its parts, which are prior to it. Moreover, since nothing puts itself together, a composed being requires an assembler, a creator, and thus cannot be the ultimate being.

Despite this, the persistence with which we talk about the various roles (another euphemism for parts) of the divine persons in the external operations of God indicates that we are bewitched to that picture of three agents cooperating and coordinating. There is a very good two-fold explanation why we cling to this picture, however. First, as a people of the book and of revelation, we apparently cannot make sense of these operations except on the model of three distinct divine agents. Secondly, and related to this, certain non-negotiable dogmas seem to be incompatible with the idea that God acts externally as a single agent: the doctrine of the incarnation of the Son alone being the most obvious one.

Let’s combine these in a set of questions: doesn’t the Bible itself portray separate agents, particularly in how they relate to one another? Doesn’t the Father speak to the Son? (Jn 17) Doesn’t the Son have to ascend first, before the Spirit comes? (Jn 7:39; 16:7) Isn’t it just the Son that has become incarnate, suffered, and died? These are exactly the kinds of objections students of theology formulate against the doctrine of inseparable operations. So deeply entrenched is this picture of the Trinity, and its coordinated operations, that the classic doctrine that God acts inseparably as a single agent has become incredible and counterintuitive.

In what follows, I would like to suggest two pictures which suggest a different imagination. Together these two images can help us understand why the objections to the inseparability doctrine arise; and they provide an alternative angle from which the objections are defused.

Expanding Our Imagination

The first image is suggested by Edwin Abbott’s 1884 novella, Flatland. In this imaginary tale, we encounter a two-dimensional being living in so-called Flatland, among other such beings, having various geometric forms: triangles, circles, rectangles, hexagons, and so on. These geometric forms are sentient beings that interact and speak with one another. Now into this two-dimensional world, a three-dimensional sphere makes its appearance. At first it only speaks to our Flatlander, who becomes conscious of a presence, at first, but sees nothing. The sphere then manifests itself to the Flatlander, at first by passing through his two-dimensional plane. At this point the Flatlander sees a circle, but one which, unusually, appears out of nowhere, then increases, and then gradually shrinks until it disappears again. The sphere explains that it is a being coming from a higher dimension and tries to explain this third dimension to the Flatlander, but to no avail. He simply lacks the categories to grasp the mystery. Eventually the sphere proceeds to lift up the Flatlander into Spaceland, giving him an experience of three-dimensional reality. The story continues, but for our purposes we have said enough – due apologies for the spoilers. I will tease out the theological lessons once I have introduced the second image.

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