Augustine: Confessing Inseparable Operations Is Orthodox Faith

Augustine's 52nd Sermon establishes "the most orthodox faith," which centres on the inseparable operations of the Father, Son, and Spirit

The doctrine of inseparable operations teaches that the Father, Son, and Spirit act inseparably in their external works. Almost nobody knows this doctrine by name today, even though many intuit its conclusion. But that should not be the case. This doctrine stood as a central pillar supporting the church’s teachings on God in years past, and its loss from our collective memory makes us vulnerable to attacks on our Trinitarian faith.

To equip us with this teaching, we can turn to Augustine of Hippo, who preached on this topic during the early years of the 400s AD.

Augustine: Inseparable Operations as the Most Orthodox Faith

In Sermon 52, Augustine preaches on the Baptism of Jesus and argues for the inseparable operations of the Father, Son, and Spirit. For Augustine, inseparable operations amount to a confession of “the most orthodox faith.”

This doctrine demonstrates how the “Father, Son, and Holy Spirit are one inseparable trinity or triad” (Sermon 52.2). It also shows how the triad is “one God in such a way that the Son is not the Father, that the Father is not the Son, that the Holy Spirit is neither the Father nor the Son, but the Spirit of the Father and of the Son” (Sermon 52.2).

Importantly, the source of this teaching is the Bible. Inseparable operations is “a summary of biblical testimonies” and is “founded on apostolic truth” because “our faith insists on this” (Sermon 52.2).

In other words, for Augustine, the doctrine of inseparable operations names a biblical teaching about the Father, Son, and Spirit, and this biblical teaching is part of the “Catholic faith.” By “Catholic,” Augustine means the church that has spread across the whole world: “It is the Catholic Church itself, called in Greek katholiké, because it is spread through the whole world” (Letter 52).

In his own words, Augustine says:

“Now someone may say to me, ‘Demonstrate that the three are inseparable. Remember you’re speaking as a Catholic, speaking to Catholics. Our faith, after all, that is to say the true faith, the right faith, the Catholic faith, which is not a bundle of opinions and prejudices but a summary of biblical testimonies, not riddled with heretical rashness, but founded on apostolic truth—our faith insists on this. This is what we know, this is what we believe; this, even if we don’t see it with our eyes, nor even with our hearts as long as we are being purified by faith, this all the same we hold with the firmest and most orthodox faith, that Father, Son, and Holy Spirit are one inseparable trinity or triad; one God, not three gods; but one God in such a way that the Son is not the Father, that the Father is not the Son, that the Holy Spirit is neither the Father nor the Son, but the Spirit of the Father and of the Son. It is this ineffable godhead, wholly self-contained, renewing, creating, re-creating all things, sending, reclaiming, judging, liberating, this then that we know to be at once both ineffably a trinity, triad or three, and inseparable’” (Sermon 52.2).

Augustine: Are the Persons Separable at the Baptism of Jesus?

Even though Augustine confesses inseparable operations as a necessary Catholic teaching of the faith, he recognizes that the Baptism of Jesus creates intellectual challenges to this position.

“So what are we to do? Here you have the Son coming separately in the person of a man, the Holy Spirit separately coming down from the sky in the form of a dove, the voice of the Father separately being heard from the sky, ‘This is my Son.’ Where now is the inseparable trinity? I see that through me God has made you very attentive. Pray for me, that while you are, so to say, opening your laps, he may grant the means of filling what you have opened. Join in the work with me” (Sermon 52.3).

The key question, notes Augustine, that eager Christians will ask is: “Does the Father do anything that the Son doesn’t do, or the Son do anything that the Father doesn’t do?” (Sermon 52.4).

To answer that question, Augustine points to the general teaching that the Father works through the Son. “All things were made through him, and without him was not any thing made that was made” (John 1:3). Here, one can see that the Father made all things through the Son (Sermon 52.4). Augustine points to this general teaching to set the stage for what exactly happens at the Baptism.

But, reasons Augustine, if the Father and Son inseparably act together, would that mean that the Father was born of a virgin, suffered under Pilate, and ascended into heaven (Sermon 52.6)? No, says Augustine. After all, “What’s in the creed? That the Son was born of the virgin, not the Father. What’s in the creed? That the Son suffered under Pontius Pilate and died, not the Father” (Sermon 52.6). Christians rejected this teaching during the early eras (i.e., they rejected the Patripassians).

Augustine: How God Works Inseparably in Scripture (Sermon 52.9–13)

While restricting himself to the Father and Son, Augustine walks through key moments of Christ’s life to show how the Father and Son act inseparably.

First, the Father and Son brought about the Son’s birth (Sermon 52.9): Galatians 4:4-5: “But when the fullness of time had come, God sent his Son, made of a woman, made under the law, to redeem those who were under the law.”

Augustine secondly demonstrates that the Father and Son brought about the virgin birth by citing (Sermon 52.11):

• Philippians 2:6-7: “Who, when he was in the form of God, did not think it robbery to be equal to God, but emptied himself, taking the form of a slave,” where taking the form of a slave refers to his Incarnation or birth.

• Galatians 4:4 & Romans 1:3: “When the fullness of time had come, God sent his Son made of a woman,” “Who was made for him of the seed of David according to the flesh,” where the Father makes the Son.

Augustine next points to the Passion of Christ as brought about by both Father and Son (Sermon 52.12):

• Romans 8:32: “Who did not spare his own Son, but gave him up for us all,” where the Father gave up his Son.

• Galatians 2:20: “Who loved me and gave himself up for me,” where the Son gave himself up.

Lastly, Augustine points to the Resurrection as the work of both the Father and Son (Sermon 52.13):

• Philippians 2:9: “Therefore he exalted him from the dead, and bestowed on him the name which is above every name” (Father exalts).

• John 2:19: “Pull down this temple, and in three days I will raise it up” (Son raises).

• Psalm 41:10: “And raise me up and I will repay them” (Father raises)

• John 10:18: “I have power to lay down my life, and I have power to take it up again. Nobody takes it from me, but I myself lay it down of my own accord, and I take it up again” (Son raises).

Augustine believes he has “proved my propositions” “with the strongest documentary evidence” (Sermon 52.14). He now summarizes the doctrine to reinforce its meaning:

“The Father wasn’t born of the virgin, and yet this birth of the Son from the virgin was the work of both Father and Son. The Father did not suffer on the cross, and yet the passion of the Son was the work of both Father and Son. The Father did not rise again from the dead, and yet the resurrection of the Son was the work of both Father and Son” (Sermon 52.14).

He continues:

“You have the persons quite distinct, and their working inseparable. So let us never say that the Father worked anything without the Son, the Son anything without the Father. Or perhaps you are worried about the miracles Jesus did, in case perhaps he did some which the Father didn’t do? Then what about ‘But the Father abiding in me does his works’ (Jn 14:10)? What I have said is plain enough; it only needed to be said. We don’t have to work at understanding it, only to take care to remind ourselves of it” (Sermon 52.14).

Augustine: Inseparable Operations within Theology

To help people understand the doctrine, Augustine reminds his congregation of the larger teachings of the church. First, he notes that one cannot locate inseparable operations in a body, since God is immaterial and not materially located (e.g., Rom 1:20; Sermon 52.15).

Second, he reminds his congregation that when we look for God in the created realm, we find that He is incomprehensible. Completely understanding this doctrine would be impossible. “So what are we to say, brothers, about God? For if you have fully grasped what you want to say, it isn’t God” (Sermon 52.16).

Using the key theological term comprehension, Augustine continues: “If you have been able to comprehend it, you have comprehended something else instead of God. If you think you have been able to comprehend, your thoughts have deceived you. So he isn’t this, if this is what you have understood; but if he is this, then you haven’t understood it. So what is it you want to say, seeing you haven’t been able to understand it?” (Sermon 52.16).

Third, Augustine points to the possibility of finding some analogy through the image of God in us and Christ being the Image of God (Sermon 52.17–18). This begins the final portion of his sermon, in which he discusses how the likeness of the Trinity might be known through humans being created in God’s image.

Augustine: Are the Inseparable Three Reflected in Man?

First, Augustine notes how humans have memory (where we store ideas), understanding (where we know our memory), and will (where we do what we choose). In simple terms, “If you didn’t have memory, you wouldn’t retain what I have said; if you didn’t have understanding, you wouldn’t be able to assess what you have retained” (Sermon 52.19). And if you did not have will, you would not be able to choose to retain and access (Sermon 52.19).

Now these three parts of man—memory, understanding, and will—act inseparably, argues Augustine, and so they provide a dim but usable created analogy to understand how God works inseparably.

“Here it is then: of those three things one was named, the name of only one of them was mentioned; ‘memory’ is the name of just one of those three. And yet all three were in operation to produce the name of one of the three. The single word ‘memory’ couldn’t be pronounced without will, understanding, and memory all operating. The single word ‘understanding’ can’t be pronounced without memory, will, and understanding all operating. Nor can the single word ‘will’ be pronounced without memory, understanding, and will all operating” (Sermon 52.21).

He continues a bit further: “All three produced the name ‘memory,’ but the only one of them it belongs to is the memory. All three produced the name ‘understanding,’ but the only one of them it belongs to is the understanding. All three produced the name ‘will,’ but the only one of them it belongs to is the will” (Sermon 52.21).

It is clear how these things can analogically be applied to the Trinity: “So too, the Trinity produced the flesh of Christ, but the only one of them it belongs to is Christ. The Trinity produced the dove from the sky, but the only one of them it belongs to is the Holy Spirit. The Trinity produced the voice from heaven, but the only one of them the voice belongs to is the Father” (Sermon 52.21).

Rhetorically, Augustine’s point is that if humans have something that operates inseparably within us, how much more plausible is it that God Himself, who is an immaterial being, does too (Sermon 52.23).

Augustine is careful to say that he does not believe the human triad equals the divine, however. “I haven’t introduced these three things as though they were to be equated to that divine triad, as though they were to be marshaled into an analogy, that is to say into a strict comparison. I don’t mean that” (Sermon 52.23).

So what does he mean? Augustine explains:

“Look, I’ve found three things in you, indicated separately, operating inseparably; and each one of those three has a name produced by the three; but it doesn’t belong to the three, only to one of them. So now believe the same about that three which you cannot see, if you have heard and seen and grasped it about this three” (Sermon 52.23).

Augustine also rhetorically notes that we might as well start by looking within, because we cannot know God as He is now. But we can know ourselves:

“What’s in you, after all, you can know. When will you ever be able to know what is in the one who made you, whatever that may be? Even if you will be able to, you certainly can’t now. And yet, when you are able to, do you think you will be able to know God in the same way as God knows Himself?” (Sermon 52.23).

Conclusion

The Baptism of Jesus does not compromise the doctrine of the trinity or inseparable operations. That the Spirit descends like a dove, the Father speaks, and the Son is baptized show how the three in their external works operate inseparably. The way in which the Holy Triad works apart from the material signs of divine action eludes us by definition since God is invisible and incomprehensible.

But as Augustine would say, we believe in order to understand. So by believing our most holy and orthodox faith in accordance with the Scriptures, we confess that the Father, Son, and Spirit while named separately work inseparately in their acts within the created world.

This doctrine sharpens up our theology so that we can withstand the coming and already presented criticisms of the biblical doctrine of the trinity. Augustine shows one way in which early Christians argued for the Holy Triad’s unified work that represents not only the oneness of God by the inseparable activity of the Father, Son, and Spirit.

If we cannot remember how the Bible teaches us about the Holy Triad, we will fail to uphold the faith when challenged by skeptics and the curious alike.

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[1] I am using the translation of Edmund Hill in Sermons, vol. 3, Sermons 51–94 (Brooklyn, NY: New City Press).