The following was written in partial fulfillment of the requirements of Dr. Steve McKinion's The Doctrine of the Trinity class at Southeastern Baptist Theological Seminary.
Rahner’s Rule famously states that “the ‘economic’ Trinity is the ‘immanent’ Trinity, and the ‘immanent’ Trinity is the ‘economic’ Trinity.”(Rahner  1997, 22) The dictum has been much debated and stands as a major point of consideration—not to say contention!—in modern Trinitarian doctrinal discussion. This paper will establish that Rahner’s rule, rightly understood and articulated,1 is correct and essential for the Christian faith, and leads inexorably to the conclusion that the names “Father,” “Son,” and “Spirit” are titles of God in being, and not only in activity. The triune actions of God are the result of his triune being; therefore, God’s work in salvation history is truly self-revelatory. Thus, Christians may claim to have right and proper, though not exhaustive, knowledge of the divine nature through his mighty works in history. The one true, Triune God has acted in history as the Father of Jesus Christ, the Incarnate Logos, and the Spirit of the Father and the Son—and in this he has not presented a charade, but the Godhead as it truly is. Thus, Christians are right to understand God as being in essence and being, and not merely in action—that is, in se—Father, Son, and Spirit.
A definition of the terms may be helpful: the “economic” Trinity is the Trinity at work in history (and especially salvation history). The “immanent Trinity” is God present to himself (in se); it might well be termed the “ontological” Trinity or “eternal” Trinity.2 Thus, Rahner’s claim entails at least 3 sub-claims: God is Trinity in being; God’s Triune nature is revealed only through (salvation) history; and God’s Triune nature is truly revealed through salvation history.3 Responses to Rahner’s dictum since its 1970 publication in The Trinity have taken it in one of two major directions: “radicalizing” and “restricting.” Authors following the radicalizing course reduce the immanent Trinity to the economic trinity. As a consequence, they often tie human knowledge of (and sometimes the actual being of) God to his development along with the cosmos, or to human experience of God in the Incarnation specifically. In constrast, the “restricting” interpreters affirm Rahner’s rule but note its limits. In particular, they tend to emphasize that the being of the Trinity is independent of salvation history, though rightly revealed in it.(Sanders 2005, 83–84) This paper takes the later stance.
Several passages in the New Testament emphasize most clearly the integral (and not merely functional) unity and relationship of the Father and the Son, and likewise the essential relationship of Spirit to Father and Son. In each case, the claim’s truth depends on the eternal relations between the persons being precisely those revealed in salvation history.4
Throughout his prologue, John is at pains to demonstrate that the Logos eternally dwells as Logos and as God—and as Son. In 1:14, John emphasizes that the glory of the Incarnate Word is as (that it: it is) the glory of the only Son from the Father. He follows this with the assertion that “the only God, who is at the Father’s side, he has made him known” (verse 18). In John 10:15, Jesus himself proclaims that he knows the Father and the Father knows him; in 10:30 he declares, “I and the Father are one.” The consistent claim of John’s gospel, then, is: Jesus, the Incarnate Logos, knew and revealed the Father as his Son. For the claim to be coherent or true, two things must hold.
First, Jesus’ knowledge of God as his Father could not merely be a statement of the state of affairs between them during the Incarnation. If that were the case, the knowledge he claims would be knowledge not of the Father as he is, but only of the human experience of God as wholly other, transcendent, unreachable—not, that is, of God as immanent. It would not be the knowledge of God as he is within his own triune self. Second, and consequentially, the revelation Jesus offered his disciples of God would likewise be not of God as he is in himself, but only the human experience of God. If God is not Father to the Son and Son to the Father in se, but only in acts in history, then the revelation of God as the “Father of our Lord Jesus Christ” (Eph. 1:3, Col. 1:3). Moreover, the apostles claimed Jesus to be “the image of the invisible God” (Col. 1:15) in whom “all the fallness of God was pleased to dwell” (Col. 1:19); the “radiance of the glory of God and the exact imprint of his nature” (Heb. 1:3). Again, if Jesus’ acts in history can be separated from his nature, these claims become meaningless. Jesus’ Sonship and his making a way to the Father are central to the apostolic preaching. If Sonship and Fatherhood are not part of God’s nature, Jesus could neither have imaged God nor carried the exact imprint of his nature.
Likewise, Jesus’ promise to ask the Father to give the Spirit (14:16–17), which finds its fulfillment after the ascension of the Son, highlights the eternal relation between the persons. Whether during or after (or indeed before) the Incarnation, the Son speaks to the Father as Father, and the Father sends the Spirit as his Spirit at the Son’s request as Son. Thus, in John 14:15–29, Jesus explains that the coming of the Spirit is the coming of the Son. To have the Spirit of truth is to have the Son who is in the Father, in oneself. The Father and the Son come to a believer when the Spirit comes to her (14:20). The Son comes to the one whom the Spirit indwells (14:21, 28). The Spirit proceeds from the Father and bears witness about the Son who sent him (15:26). But as with the persons of the Son and the Father, this identity cannot be if the persons are not merely acting in this way, but rather eternally subsist, eternally are being the Father of the Son and Son of the Father and Spirit of the Father and the Son. How could the Spirit bear witness truly to the Son, or rightly be said to be sent by the Father, if the Son and Father are not actually Son and Father, but only act as such in the history of salvation? In that case, the Spirit might be sent in salvation history, but would not bear witness to the Son as he is in himself. The revelation would be of something less than God—not at all what Jesus promised.
In each case, it is clear: Scripture claims that the actions of the Triune God in history reveal him as he is. The Son truly reveals the Father. The Father truly sends the Spirit through the Son. The Spirit truly glorifies the Father and the Son. These are so because the Spirit, Son, and Father act in accordance with their eternal, immanent relations. The efficacy of God’s reconciling, saving work—the Son drawing people into his own communion with the Father through the indwelling Spirit—depends on the economy of salvation being the outworking of God’s own nature. Their relations within the Godhead which precede, ground, and perfectly inform their actions. Thus, Rahner’s rule might helpfully be elaborated and rephrased: the economic Trinity (rightly and truly, but inexhaustively) reveals the immanent Trinity, because the economic trinity derives wholly from the being of the immanent Trinity. Being drives action, and action (partially, but truly) reveals being.
Though Rahner’s Rule is strictly correct, his own elaboration of these ideas has its limits: not least in its tendency, as he developed it, toward modalism.5 Thus, Letham observes that Rahner’s discussion of persons as “distinct manners of subsisting” leaves little room for love between the subsisters.(Letham 2004, 295–96) However, the solution is not to abandon Rahner’s dictum, but to press on it more firmly, more clearly, and more Scripturally. After all, the Scriptures bear witness to the triune God’s actions precisely as their interacting not merely as “subsistences” but as persons-who-love. The Son does the Father’s will and shows the Father truly, and they send to their people the Spirit who communicates everything of the Father and the Son. As Torrance comments:(Torrance  2006, 53)
Thus when we approach God as Father through the Son, our knowledge of the Father in the Son is grounded in the very being of God and is determined by what he essentially is in his own nature… in Jesus Christ we are really enabled to know God in accordance with his own nature as Father and Son…
But this is not the case if the economic Trinity and the immanent Trinity are truly distinct. The Incarnation reveals God as he is in himself only if the God’s works flow from his being and essence, in the relations Father, Son, and Spirit.
Likewise, Letham is right that Rahner partially neglects the immanent Trinity and limits himself to the human experience of the economic Trinity.(Letham 2004, 297) For example, Rahner regularly falls prey to a trap Athanasius avoids: seeing the Father, especially in the Old Testament, primarily as unoriginate.6 Worse, he derives the person of the Father from the knowledge of the Father.(Rahner  1997, 60) He fails to apply the second half of his dictum. If the first half emphasizes that the Trinity’s actions reveal the divine being, the second half emphasizes that those actions flow out of the divine being. The acts of the Godhead in history reveal to God’s nature because they are not merely human experiences, but the God’s self-revelation of his own being.
Rahner largely has the right of this elsewhere. He notes that when Jesus considers himself as Son, he considers not only his human but also his divine relation to the Father as that of a Son.(Rahner  1997, 63–65) The incarnate Son reveals both the Father truly, and also that the Incarnate Logos is Son and not Father.(cf. Rahner  1997, 29 and @torrance, 55) The same must be said of the human relationship to God through the Spirit.(Rahner  1997, 67) The Spirit who communicates the love and grace and forgiveness the Father has effected by the work of the Incarnate Son is God. He communicates God as he is, as the presence of the Father’s self-revelation in the Son.(Torrance  2006, 203) The Spirit is the Spirit of the Father and the Spirit of the Son; he is the true presence of both; he shares their mutual love and joy, and communicates both to believers.
John Frame objects to another misstep Rahner’s rule might prompt: “There is a difference between what God is necessarily and what he freely chooses to do in his plan for creation.”(Frame 2002, 2:706–7) No necessity demanded creation, salvation, or indeed any of God’s acts in history.(Letham 2004, 363–64; Torrance  2006; Barth 1956b, I.2:135) They are gifts.(Barth 1956a, IV.1:52) They are acts in which the Trinity is evidenced, and therefore are truly revelatory; but this is because God faithfully acts in accord with his own nature.(Letham 2004, 296; Barth 1957, II.1:57–58) On the other hand, the realities of the Trinity “either are in God himself… or they exist only in us… as effects of the divine creative activity. But then… there occurs no self-communication, God himself is not there, he is only represented by the creature…”(Rahner  1997, 100) God is not obliged to act in a particular way in salvation history, but his actions truly reflect his being. It is because “God is, ‘before’ creation took place, already a being-in-relation”(Gunton  1997, 142) that he is free of necessity in creation or salvation. The Trinity does not need anything, for Father, Son, and Spirit are eternally in relation to one another. God does not need to create, to redeem, even to reveal himself; “God’s self-unveiling remains an act of sovereign divine freedom”(Barth  1975, I.1:321)—but creation, redemption, and revelation are still acts of self-unveiling.
Thus, if Rahner’s rule is pressed to the point where God’s triunity is restricted to (or by) his acts in history, it is wrong, for precisely the reason Frame outlines—but it need not be pressed that way. “The Triune God is the Lord of history. Events in this world do not prescribe his being, or his tri-unity… all we know of the immanent Trinity is given in revelation, but revelation does not and cannot fully reveal God to human minds.”(Giles 2006, 258) The Father of Jesus is the eternal Father of the Son, the incarnate Logos the eternal Son of the Father, and the sent Helper is the eternal Spirit of Father and Son. Human knowledge of the Trinity is not exhaustive, but it is true. “God reveals himself as he truly is… the economic roles played by the three persons must be appropriate to their natures.”(Frame 2002, 2:706)
One other serious challenge remains. How (if at all) should Jesus Christ’s human nature be taken to relate to his divine nature in considerations of the correspondence or identity7 between the economic and immanent Trinity? The Incarnation reveals the relationship of Father to Son and Son to Father (as well as the relation of the Spirit between the two); then is everything that is true of the way that the Son/Logos-as-man related to the Father true of the way that the Son/Logos eternally relates to the Father? Or are there instead elements of the Incarnation which reflect Jesus’ human as well as his divine nature in relation to the Godhead? It is clear that Jesus the man subordinated his will to God the Father’s will, but it is not at all clear that this entails the eternal submission of the divine Son’s will to the Father’s will. Whether in liberationist theology or attempts to ground male-femlae relations in the ontology of the Trinity, any “radicalizing” approach tends to collapse the proper direction of the identity. It does not follow from the eternal distinction between Father and Son that the Father’s love for the Son is somehow greater than than the reciprocal love of the Son for the Father, or that the creative and redemptive acts of the Trinity in history reflect such a distinction.(contra Moltmann 1992, 39)
Was it necessary in a logical or ontological sense that the Son and not the Father or the Spirit become incarnate? The answer is “yes”, but a carefully qualified yes. Creation, salvation, and eschatological restoration are each acts of the Triune God in which there is no confusion of that which is outside the Trinity and the inner Triune life itself.(Barth 1958, III.1:54–55) The Father wills, and through the Son’s action the Spirit effects. But in each of these acts, it is the Father as Father, the Son as Son, and the Spirit as Spirit at work.(Barth 1958, III.1:56) Not only in the specific instance of Incarnation, but in all of history8 the economy of the Trinity reflects and proceeds from the essence of the Trinity.(Rahner  1997, 76) God freely acts in history in accord with his own being.(cf. Letham 2004, 418; Rahner  1997, 11–12; Frame 2002, 2:711–12) At the same time, the Incarnation—however climactic—is not the whole of God’s self-revelation. Equally important must be both the rest of salvation history and the apostolic teaching on the nature of the Son, which clarifies: there is mutual submission within the Trinity.(Frame 2002, 2:719) It was fitting that the Son be Incarnate, and the Spirit sent; but more than this in terms of subordination should not be read into the relations of the Trinity.
If the persons of the Trinity are not Father, Son, and Spirit in and of themselves, then Christians know nothing of the inner life of the God we profess to worship. The notion of Scripture as divine self-revelation is a sham. The actions of God in history do not reveal God himself. In that case, Jesus’ claim to reveal the Father would be more than suspect; it would be false. Moreover, it must have been the Son, the Logos, who was the climactic revelation of God (Heb. 1:3), and the Spirit who is the indwelling presence of Father and Son in God’s people. “The divine Word is the divine speaking. The divine gift is the divine giving.”(Barth  1975, I.1:321)
Barth, Karl. 1956a. The Doctrine of Reconciliation. Edited by G. W. Bromiley and T. F. Torrance. Translated by G. W. Bromiley. Vol. IV.1. Church Dogmatics. Edinburgh: T & T Clark.
———. 1956b. The Doctrine of the Word of God. Edited by G. W. Bromiley and T. F. Torrance. Translated by G. W. Bromiley. Vol. I.2. Church Dogmatics. Edinburgh: T & T Clark.
———. 1957. The Doctrine of God. Edited by G. W. Bromiley and T. F. Torrance. Translated by T. H. L. Parker, W. B. Johnston, Harold Knight, and J. L. M. Haire. Vol. II.1. Church Dogmatics. Edinburgh: T & T Clark.
———. 1958. The Doctrine of Creation. Edited by G. W. Bromiley and T. F. Torrance. Translated by J. W. Edwards, O. Bussey, and Harold Knight. Vol. III.1. Church Dogmatics. Edinburgh: T & T Clark.
———. (1936) 1975. The Doctrine of the Word of God. Edited by G. W. Bromiley and T. F. Torrance. Translated by G. W. Bromiley. Second edition. Vol. I.1. Church Dogmatics. Edinburgh: T & T Clark.
Erickson, Millard J. (1995) 1996. God in Three Persons: A Contemporary Interpretation of the Trinity. Second printing. Baker Books.
Frame, John. 2002. The Doctrine of God: A Theology of Lordship. Vol. 2. A Theology of Lordship. Phillipsburg: P&R Publishing.
Giles, Kevin. 2006. Jesus and the Father: Modern Evangelicals Reinvent the Doctrine of God. Grand Rapids: Zondervan.
Gunton, Colin E. (1991) 1997. The Promise of Trinitarian Theology. Second edition. T & T Clark.
LaCugna, Catherine Mowry. (1991) 1993. God for Us: The Trinity and the Christian Life. First paperback edition. New York: Harper San Francisco.
Letham, Robert. 2004. The Holy Trinity: In Scripture, History, Theology, and Worship. Phillipsburg: P&R Publishing.
Moltmann, Jürgen. 1992. History and the Triune God: Contributions to Trinitarian Theology. Translated by John Bowden. New York: Crossroad.
Rahner, Karl. (1967) 1997. The Trinity. Translated by Joseph Donceel. March 2015 printing. New York: The Crossroad Publishing Company.
Sanders, Fred. 2005. The Image of the Immanent Trinity: Rahner’s Rule and the Theological Interpretation of Scripture. Issues in Systematic Theology 12. New York: Peter Lang.
Torrance, T. F. (1991) 2006. The Trinitarian Faith. Paperback edition, sixth printing. New York: T & T Clark.
Which is not necesarily to say “as Rahner himself understood or articulated it” or “as it is interpreted by his most famous interpreters”.↩
For a helpful summary of the history of the development of the terms, see Giles (2006) 246–249.↩
For a similar summary of this development, see Giles (2006) 250–265.↩
“Precision” here meaning “truth” but not “exhaustion.” See below.↩
Cf. Rahner ( 1997) 106–107, where Rahner very nearly collapses the persons into the mere self-expressions of a pure monad.↩
E.g. (Rahner  1997, 59); cf. Athanasius Apologia Contra Arianos 1.33–34.↩
On “correspondence” and “identity” cf. Giles (2006), ch. 7.↩
In some sense, given the fall and God’s action to restore and redeem humanity, all history is salvation-history.↩