Is the Filioque Clause Biblical?

The latest edition of our Foundations theological journal was published at the end of November. It contains articles and book reviews of help and encouragement to those wanting to engage with scripture and theology at a deeper level, yet still being practical and applied.

One such article is ‘Is the Filioque Clause Biblical?’ by Jake Eggertsen:

“I believe in the Holy Spirit, the Lord, the giver of life, who proceeds from the Father and the Son…”

Does the Holy Spirit proceed from the Father and the Son as Western versions of the Nicene Creed say? Why does it even matter? This article argues that the Filioque clause is not just part of our creedal heritage, but a biblical concept arising out of theological reflection on the relationship between the economic Trinity and the immanent Trinity. It should therefore play an essential role in our contemplation and worship of God, the Holy Trinity. Methodologically, this article is an exercise in constructive dogmatics, examining the key exegetical and theological decisions needed to construct a case for the double procession of the Holy Spirit from the Father and the Son.[1] As part of this, a central matter to address is the extent to which the economy of the Spirit’s mission reveals immanent, eternal, and triune processions.

For Jaroslav Pelikan, the early Filioque debates were marked by a failure to sufficiently distinguish between “immanent” proceeding and “economic” sending.[2] However, this was far from the only cause. For a variety of reasons, this centuries-old debate has been the subject, source and symbol of considerable conflict between the Church East and West.[3] One key issue is legitimacy. Did the Church have the authority to alter the received Niceno-Constantinopolitan Creed when it inserted the Filioque into the text? Many appeal to Canon 7 from Ephesus I (431), which forbids changes to the Spirit-inspired Creed of Nicaea, to suggest it did not.[4] Despite this, though it was not officially adopted at Rome until the eleventh century, there is proof of its formal use as early as Toledo III in 589.[5] Another reason for the Filioque’s considerable influence was its capacity and utilisation as a weapon for power.[6] However, although these historical and ecclesiological dimensions are integral aspects of the doctrine’s development, this is not what I intend to discuss here. 

It is my contention that the doctrine of the double procession of the Spirit is biblical. Yet, in terms of method, one cannot simply appeal to exegesis alone to resolve the question. Constructing a case for the Filioque involves arguments, concepts, language and categories that go beyond individual texts. In other words, it requires Dogmatic Theology, helpfully defined by Fred Sanders as, “conceptual representation of scriptural teaching about God and all things in relation to God.”[7] That is not to suggest this reflection is outside of biblical revelation. Rather, it is what Glenn Butner calls, “second order reflection that draws on philosophy to provide conceptual clarity concerning who God must be or what God must have done, given scriptural teaching.”[8] One might add that proper theological enquiry also requires reflection upon the canon as a whole.[9] Accordingly, the ambition of part I of this article is to move between dogmatic considerations and the biblical text, bringing one into conversation with the other, guided by the classical faith in the tradition of Augustine and Aquinas. Part II provides several further implications of the Filioque clause for constructing trinitarian theology and the life of faith, before forming a brief conclusion.

I.         “Like begets like”[10] – Missions, processions and The Filioque

A crucial step in establishing a case for the double procession of the Spirit is recognising the relationship between communicative missions and processions.[11] This is not a straightforward exercise. The route taken here involves many steps. First, I will outline a definition and description of communicative missions. After that, by way of a brief excursus, it is necessary to discuss the implications of the “analogical interval” for our knowledge of God. Only then can we determine what may be said of God in terms of reading the missions back into the internal processions. Finally, having established some principles, a case will be made for the Filioque as a biblical concept.

1)     Communicative Missions

The term Communicative missions refers to the visible and verbal revelation of the divine life of God in the economy of salvation, most noticeably in the incarnation and Pentecost. However, as Thomas Aquinas notes, these two events cannot be conflated. For, unlike the Son’s incarnation, the Spirit does not take on a hypostatic union with the corporeal signs, for example doves or tongues of fire, that signify his presence.[12] Neither should these missions be seen as solo performances of the Son and Spirit respectively. Rather, the persons work inseparably in the activity of the economy. In the patristic era, this was commonly described using the analogy of light, drawn from Psalm 36:9: “For with you is the fountain of life; in your light we see light.”[13] Alluding to that verse, Gregory of Nazianzus writes:

The Father was the True light which lightens every man coming into the world. The Son was the True light which lightens every man coming into the world. The Other Comforter was the True Light which lightens every man coming into the world.[14]

The point is, whilst the person of the Son might be “hypostatically visible” in the incarnation, all three persons nevertheless work without division.[15] We see this vividly expressed in the harmony of Matt 3:16-17. The incarnate Jesus is the focal point of the narrative as he ascends out of the water at baptism. Yet, in that moment, the Spirit alights on him, anointing him with power, and the Father’s love and will is revealed in the “voice from heaven”. Thus, following Augustine, the incarnation is not just a Christological but a Triune act.[16]

What is more, the missions are not simply actions or events executed by God but are in themselves a real revelation of the Triune God. As Fred Sanders affirms: “God put himself into the gospel”,[17] and the missions are the “image of the immanent Trinity”.[18] In other words, missions are visible extensions of the invisible inner divine life. That said, Sanders’ use of the word “image” does not imply a strictly identical relationship between economic and immanent, which, depending on one’s interpretation of it, is the essence of Rahner’s rule.[19] Contra Rahner, what Sanders in fact proposes is both an indelible link and a distinction between the ad extra and the ad intra life of God. The link safeguards participation in the real.[20] Channelling Hans Boersma (himself drawing on Augustine), there are “eternal realities” truly present in the earthly, visible things.[21] From the creature’s perspective, God is knowable by these signs.[22] Yet, the distinction is also vital because it wards off constructing a doctrine of the Trinity from certain conditions and accommodations in the economy, which are designed to stay in the economy.[23]

2)     Knowledge of God’s Being

Before moving to consider God’s internal processions, it is necessary to explore the foundational reason for the economic-immanent distinction. It is an ontological one: God’s being and our being are not univocal. Indeed, God is (perfect) being itself.[24] He is pure actuality (actus purus). This means that God does not have or possess perfections, he is his perfections.[25] On the other hand, human beings are created, complex, changeable. The connection between our being and God’s being is therefore only by analogy (analogia entis). By analogy I mean “linguistically mediated correspondence”,[26] and not, as Colin Gunton argues in favour of, any sense of univocal correspondence between God and creatures.[27]   

A common objection to this type of description of God’s perfect being is that it leans too heavily on Greek philosophy rather than Scripture to build a dogmatic account of the Trinity.[28] Yet, that is to commit the genetic fallacy.[29] “Classical Theism”,[30] which encapsulates the metaphysical commitments of Aquinas et al, has unashamedly utilised concepts from Plato and Aristotle. Yet it has adopted them as servants, not masters, in the task of second-order reflection upon, and disciplined by, God’s revelatory word. Moreover, as many have ably shown, every theologian has metaphysical assumptions that guide and shape their interpretation of reality and the Christian faith.[31] The key question is, are they honest and suitable ones? Classical Theism is not immune to critique or reform by Scripture. Yet, I would argue, it simply provides a theocentric, sanctified way of framing and speaking about God’s transcendent nature from the perspective of creatures. In fact, Aquinas himself provides a virtuous example of honest “theological metaphysics”.[32] Matthew Levering writes: “Aquinas deployed metaphysical (theocentric) analysis to raise or convert the mind to the self-revealing God who is triune spiritual substance and uncaused cause of all things.”[33]

Employed in this way, perfect being theology has important implications for our knowledge of God ad intra. Whereas God’s mode of knowledge is identical with his perfect being, human knowledge is discursive and dianoetic.[34] Put more plainly, because God is simple and absolute, dwelling in unapproachable light (1 Tim 6:15-16), so his knowledge is undivided and simultaneous: “the single and simple vision of everything”.[35] Moreover, because God is “holy, holy, holy” and utterly transcendent (Isa 6), he is not at all dependent on creation for knowledge. All of these attributes (and more) describing God’s fullness and perfection of being necessarily make God incomprehensible to human-beings: “his greatness no-one can fathom” (Psalm 145:3). In contrast, as creatures, human beings are limited and confined in space and time, completely contingent. In fact, the possibility and actuality of creaturely theology wholly rests on God knowing himself and all things.[36] Though we can know God truly and actually, our knowledge is entirely accommodated and never total, for it is an accidental, not essential, property of our being.

In a nutshell, there exists an “analogical interval” between God and creatures:[37] his thoughts are not our thoughts, nor are his ways our ways (Isa 55:8). This necessitates a right sense of mystery in our suppositions regarding God’s very nature. Our theology is both contingent on God’s external revelation and provisional in its conclusions because we cannot contain the infinite God in our knowledge of him (1 Kings 8:27).[38] Consequently, as Thomas Weinandy fittingly puts it, our “growth is in coming to know what the mystery of God is and not the comprehension of the mystery”.[39] However, far from consigning us to silence, the fact that our greatest thoughts of God never exceed his greatness ought to inspire worship, contemplation and further theological reflection.

3)     Processions

Building on all that has been said, the term procession signifies internal origination from one person to another in the Trinity. Contra Arianism, procession is not necessarily a temporal, creaturely activity. Instead, as Karl Barth argues, the language of proceeding is first meant to act as a negation to suggest a non-creaturely communication of the divine essence.[40] He writes: “what proceeds from God can only be God once again”.[41] Indeed, procession denotes “eternal communication… of the same (divine) essence”,[42] the forthcoming of God from God. So, the Son who is begotten, says Gregory of Nazianzus, is from the Father (the Father is the “cause”), but he is not after him.[43] Likewise, the Spirit proceeds from the Father and the Son, not after them. That from-not-after distinction is crucial because it preserves the differentiation of the three persons, distinguishing them according to their relations. It also serves to uphold the equality and oneness of the Godhead because divine persons are consubstantial, subsisting in the same nature.

A key passage often cited in relation to this is John 5:24-29, where Jesus himself conveys the communication of essence from Father to Son: “as the Father has life in himself, so he has granted the Son also to have life in himself” (John 5:26). Given the distinct Danielic overtones, in conjunction with the concepts of “life” and “eternal life” generally in John’s gospel, Jesus unmistakably uses ontological categories to make his point.[44] That is, because both the Father and Son possess the quality of having “life in himself”, Jesus has the divine authority to carry out the work of the Father. Together with the given/granted language in both Daniel and John 5, the passage strongly supports the doctrine of the Son’s eternal generation from the Father.[45] Contra Robert Reymond who denies the doctrine altogether, arguing that John 5:26 merely refers to “an aspect of the incarnate Son’s messianic investiture”,[46] John 5:26 in fact provides the ontological basis for the Son of Man’s function and mission in Dan 7 and 12. By reading canonically, we come to see how the Son’s incarnate role prefigured in Daniel is illuminated and magnified by the eternal relations made explicit in John. It is therefore entirely valid and appropriate to use John 5:26 in support of Thomas’ principle that “communication must be the same as what is communicated”.[47] For, though published in the economy, this passage nevertheless draws our attention to the res:[48] what is true of the Father is also true of the Son, except for his paternity.

4)     The Filioque in Scripture

At this point we might rightly ask: what of the Holy Spirit in this dynamic?[49] Where are the texts related to his procession from the Father and the Son? There is no doubt that such texts are limited. For Thomas, they do not even exist, at least per verba (by words). But that is incidental; constructive dogmatics is not an exercise in counting proof-texts. More significant is that the rule and principle established in the biblical case for the eternal generation still applies. Put differently, the Filioque is the natural and implicit corollary of the Son’s procession from the Father. So, whilst texts about the Spirit’s double procession are sparse, the concept (per sensum) of indivisible unity in God’s substance remains. Through that, we can at least affirm that whatever we say about one person must apply to the others except for relational opposition.[50] However, by that we should not conclude that the Holy Spirit is simply another Son. Nor do we need to endorse Thomas Weinandy’s anti-sequentialism.[51] Instead, what we need to ask is: what exactly do the missions in the economy reveal, if anything, of eternal, immanent causality, and in particular, the double processions of Spirit from the Father and the Son?

Thomas’ route for endorsing the Filioque begins with and largely depends on the Son’s eternal generation. If “all that belongs to the Father” also belongs to the Son (John 16:15) that necessarily includes the spiration of the Holy Spirit.[52] However, Anselm anticipates a problem here: why should the Spirit proceed from the Father and the Son and not the Son from the Father and the Spirit?[53] For him, this puzzle is solved by distinguishing generation from “procession” (by which he means spiration) – in a causal sense, one is prior to the other. Additionally, Anselm points out that the name “Holy Spirit,” as a relational designation, implies that he is the Spirit of someone. So, it cannot be that Son proceeded from the Holy Spirit because that would make him “the Spirit of the same Holy Spirit”.[54]

More substantially, Aquinas helps to define the nature and outline the logic of the distinction between generation (filiation) and spiration using the language of “intellect” and “will”. “The concept of intellect”, writes Aquinas, “is a likeness of the object conceived, and exists in the same nature, because in God the act of understanding and His existence are the same.”[55] Hence, since God is pure act, intellectual proceeding results in the Son’s generation, who is identical to the Father in all ways except for paternity. However, the Spirit’s origin in eternity is not in an act of the intellect (as per the Son’s generation) but an act of “will”, also known as the “procession of  love”.[56]  Using Augustine’s language, the Spirit proceeds from the “mutual love of Father and Son” and the “consubstantial  bond which unites them”.[57] Aquinas adds even more weight to this argumentation by examining the economic relationship between the Son and the Spirit.[58] The fact that the Son sends and gives the Spirit,[59] that the Holy Spirit is said to be the Spirit of the Son,[60] and that the Spirit glorifies the Son,[61] implies a logical sequence of relational origination in eternity: “for everything which is from another manifests that from which it is.”[62]

Some see Isa 48:16 as a difficult text in this regard, taking it to refer to the Spirit sending Christ, reading ruach as the subject rather than the object.[63] Even assuming it is the correct interpretation grammatically – this is “unlikely” according to John Oswalt[64] – does it undermine the argument that double procession is reflected in the biblical language of the sending of the Spirit by the Father and the Son? I would argue not. For, as has already been established, the economic sending of the Son is always the “joint work of Father, Son, and Spirit.”[65] Moreover, illuminated by the gospels, we see how the Spirit anoints and bestows grace upon the incarnate Christ’s human life and ministry. In that respect, it is entirely right to affirm that the man Jesus was, from one aspect, sent by the Spirit. Nevertheless, the order of the Son and Spirit’s distinctive missions (incarnation then Pentecost), revealed in Scripture as central moments in the unfolding gospel economy, must be given priority as reflections of the divine taxis in eternity. The Spirit’s  activity in the economy prior to his mission at Pentecost need not undermine this principle.

John 15:26 is integral text to consider more positively and specifically. On the surface, there appears to be only direct reference to the Spirit’s procession from the Father (“the Spirit of Truth who goes out from the Father”). Yet, as Richard Muller shows, the Reformed exegetes consistently used the verse to demonstrate the procession of the Spirit from the Son.[66] How? By the Divine Son’s affirmation that he will authoritatively send the Spirit from the Father. John Calvin writes that Christ “mentions the Father in order to raise our eyes to the contemplation of his Divinity.”[67] In other words, the verse denotes an inseparability in action between the Father and Son, which is indicative of an eternal reality. Moreover, the reference to the Spirit going out from the Father is not an exclusive statement of singular spiration. Rather, it simply acts to affirm the authority and divinity of the Spirit. So, according to Calvin, to deny the Spirit’s procession from the Son by this verse is “idle” and lacking in subtlety.[68]

Arguments for the double procession of the Spirit need not just be drawn from the NT. Christopher Seitz insightfully shows how this is the same pattern as the Spirit’s mission in the OT. He argues that the agency of the Spirit, who “spake by the prophets”, is to be deferential, constantly pointing away from himself. He is the “hand of God”, whose “vocation is to place Israel’s and the Church’s hand in the hand of their Lord”.[69] This is bolstered by the numerous OT passages which refer to the Holy Spirit as “given”.[70] Taken in corres-pondence with the account of the Spirit’s  mission in John’s Gospel (and the NT generally), this aids our comprehension of how the hidden, immanent Trinity is manifested in the economic Trinity: the missions appear characteristic of the order (taxis) of procession.[71] The Spirit can only be sent by the Father and the Son in the economy because the Spirit proceeds from the Father and the Son in eternity.[72]

For the sake of clarity, none of this implies two principles of spiration, one from the Father and one from the Son.[73] Rather, because of their equality of nature and Aquinas’ principle of “subsistent relations”, [74] we can say that the Spirit proceeds from the Father and the Son as one cause. The Father and Son relate to the Spirit in an identical way. However, this is not an “impersonal amalgam”.[75] First, it is not impersonal because, as Levering states, “the Son spirates precisely as one begotten by the Father”.[76] Incidentally, this also preserves the monarchy of the Father; he remains the sole principle of origin. Second, neither is it an amalgam because, although there are two spirating persons, the spiration is “one act that the Father and Son truly share, due to the Father’s communication of spirative power to the Son”.[77]

In conclusion, the doctrine of the double procession of the Spirit rests upon certain key principles, and not simply isolated verses.[78] Most integral is the way in which the economic Trinity, as image, truly but not exhaustively communicates the Immanent Trinity to finite creatures. In the economic activity of the Son and Spirit, the Triune God operates characteristically according to his nature. The missions are, as John Webster beautifully puts it, simply “the overflow of God’s wholly realized life as Father, Son, and Spirit.”[79]

II.         Implications and conclusion

Following this theological and exegetical undertaking, a key question remains. Namely, does it really matter that the Spirit proceeds from the Father and the Son? What does the Filioque, and the constructive dogmatic task used to defend it, actually contribute towards our Doctrine of God and the life of faith? There are at least three implications we can derive from this study.

First, theologically, the Filioque preserves the unity of substance in the Trinity. Herman Bavinck contends convincingly that “the confession of the Trinity is the heartbeat of the Christian religion. All error is traceable to a departure from this doctrine.”[80] By maintaining the doctrines of eternal communication, consubstantiality and relations of origination by opposition, the Filioque clause provides significant weight against imbalanced versions of the One and the Three, the Three and the One.[81]

One such contemporary form of divergence from the classical model lies in so-called social trinitarianism. Associated with the likes of John Zizioulas,[82] Jürgen Moltmann,[83] Miroslav Volf,[84] Colin Gunton,[85] and Wolfhart Pannenberg,[86] social trinitarianism is characterised by a relational ontology, an articulation of God’s being in terms of love, community and divine perichoresis. In reaction to what they see as an over-emphasised Augustinian sense of oneness in God, social trinitarians take the three as their starting point.[87] Essentially, the persons in communion constitute the being of God.[88] Thus, Moltmann writes of “the most perfect and intense empathy” between the persons.[89] And this, says Karen Kilby, has become the “new orthodoxy.”[90] The problem, following Kilby, is the social trinitarian notion of personhood. She rightly argues that social trinitarian theologians are often “projectionist” – explaining the divine unity from a particular form of personalism drawn from human relationships, which ultimately assumes that each person is “an isolated being over against all others”.[91] At its best, such an approach results in advocating three personal principles, or wills, in God.[92] At its worst, this amounts to tritheism. What the Filioque offers in response is a strong affirmation of the pro-Nicene concepts of homoousios, co-equality, and a distinction of the Triune persons.

Second, hermeneutically, the Filioque aids our approach in reading Scripture aright. This relates to the danger of projection highlighted above. Drawing on Charles Taylor’s contention that the immanent frame, common to all in the modern West, can “slough off the transcendent”,[93] the hermeneutical steps required to construct the doctrine of the double procession of the Spirit preserves God’s otherness. Because of the analogical interval, which arises out of divine attributes as expressed in the classical tradition, we must deny the identical correspondence between missions and processions a la Rahner. Though it may be close, it is nevertheless a differentiated relationship.[94] Our danger, if we so focus on the economic to the exclusion of the immanent, is that we undermine God’s holiness. As a consequence, we might skew ontological descriptions of God’s  nature in Scripture. Furthermore, James K. A. Smith (among others) rightly stresses how we conform ourselves, including our theology, to what we love.[95] While some have raised important questions about Thomist metaphysics, anthropocentric conceptions of love and relationships risk making God into our own image. 

Third, spiritually, this undertaking of constructive dogmatics, shaped by the classical tradition, cultivates theocentric contemplation of God. This attempt at building a biblical account of the double procession of the Spirit has clear limitations, not least because we are ascribing to God that which we cannot see and know absolutely. God is invisible and incomprehensible. Yet, the limitations of dogmatic theology do not prohibit its practice. In fact, they encourage it. For in them we are re-orientated and, paradoxically, moved to contemplate the promised, eschatological vision of God. Thus, the very task of constructing a dogmatic account of the Filioque is beneficial in and of itself. Since, through the exercise, we are moved towards one of the central promises and pledges of the gospel: “they will see his face” (Rev 22:4).[96]

Conclusion

Within our current historical location, it is not difficult to see why the classical model of the Trinity is unattractive to many. Muller is no doubt correct to suggest that there is a great deal of critique of scholasticism without much familiarity with the scholastic material.[97] A more significant reason flows from Charles Taylor’s assessment of the West. In his language, our immanent frame in this increasingly libertarian, individualistic climate makes us naturally attracted towards univocal thinking about God. For many, especially those persuaded by a social model of the Trinity, Aristotelean-Thomistic meta-physical categories therefore seem cold and unloving. Yet, what we have seen in this constructive dogmatic case for the Filioque is that the classical theistic assumption that God is perfect being and ontologically other actually means that he is maximally and supremely good. Far from a creaturely projection of personal relations, God, in the unity and “reciprocity of paternity, filiation and spiration”,[98] is infinite and full. Thus, the fact that the inner details of the Triune life are inaccessible to us is a good thing; it merely declares the ineffability and majesty of God in himself. This ought to stimulate worship. And the Filioque clause provides us with some of the grammar for that.

Jake Eggertsen is Curate at St Paul’s Church, Banbury.

 

Footnotes:

[1] “Constructive Dogmatics” is not identical with systematic theology, historical theology or theological retrieval. With Oliver Crisp and Fred Sanders, I take it that it is a task that seeks to “engage with Scripture and the tradition, dialoguing with interlocutors dead and alive, in an attempt to provide constructive resources for contemporary systematic theology”. See the introduction to Oliver Crisp and Fred Sanders, eds., Christology: Ancient & Modern Explorations in Constructive Dogmatics (Grand Rapids, MI: Zondervan, 2013), 13-14.
[2] See, e.g. the example of Marcellus of Ancyra in Jaroslav Pelikan, The Emergence of the Catholic Tradition: 100 – 600, The Christian Tradition: A History of the Development of Doctrine 1 (Chicago, IL: University of Chicago Press, 2007), 212.
[3] Vladimir Lossky pronounced that the Filioque was “the sole dogmatic grounds for the separation of East and West. All the other divergences, which, historically, accompanied or followed the first dogmatic controversy about the Filioque, in the measure in which they too had some dogmatic importance, are more or less dependent upon that original issue.” See Vladimir Lossky, In the Image and Likeness of God, ed. John H. Erickson and Thomas E. Bird (Crestwook, NY: St. Vladimir’s Seminary Press, 1985), 71-72.
[4] For historical examples, see A. Edward Siecienski, The Filioque: History of a Doctrinal Controversy (New York, NY: Oxford University Press, 2010), 5.
[5] There is some debate about when the Filioque clause first appeared in creedal form. Yet, Toledo III is the most recognised early use of the term as part of the Western version of the Nicene-Constantinopolitan Creed. See, Siecienski, The Filioque, 68. However, Gerald Bray has highlighted earlier examples of the concept in Epiphanius (writing about 374), expressed in almost identical ways to the final form of the Filioque clause: “I dare to say that… (nobody knows) the Spirit except the Father and the Son, from whom he proceeds and from whom he receives. And (nobody knows) the Father and the Son, except the Holy Spirit who is from (παρά) the Father and from (ἐκ) the Son.” See Gerald Bray, “The Filioque Clause in History and Theology”, TynBul 34, (1983): 107.
[6] Siecienski cites the exchange between Cardinal Humbert and Patriarch Michael Cerularius in 1054 as a clear example of this, in Siecienski, The Filioque, 5.
[7] Fred Sanders, The Triune God, New Studies in Dogmatics (Grand Rapids, MI: Zondervan, 2016), 15.
[8] D. Glenn Butner Jr., The Son Who Learned Obedience: A Theological Case Against the Eternal Submission of the Son (Eugene, OR: Pickwick Publications, 2018), 9. Emphasis mine.
[9] Cf. Michael Allen, “Knowledge of God”, in Christian Dogmatics: Reformed Theology for the Church Catholic, ed. Michael Allen and Scott R. Swain (Grand Rapids, MI: Baker Academic, 2016), 26.
[10] Christopher R. J. Holmes, The Holy Spirit, New Studies in Dogmatics (Grand Rapids, MI: Zondervan, 2015), 98.
[11] “Communicative Missions” is a term appropriated from Fred Sanders, The Triune God, 69. Cf. Aquinas, Summa theologiae, Ia.43. 
[12] Aquinas, Summa theologiae, Ia.43.7 ad 2.
[13] See Stephen R. Holmes, “Trinitarian Action and Inseparable Operations: Some Historical and Dogmatic Reflections”, in Advancing Trinitarian Theology: Explorations in Constructive Dogmatics, ed. Oliver Crisp and Fred Sanders (Grand Rapids, MI: Zondervan, 2014), 64.
[14] Gregory of Nazianzen, “The Fifth Theological Oration”, ed. Philip Schaff and Henry Wace, NPNF (Grand Rapids, MI: Eerdmans, 1974), Oration XXXI.iii (NPNF 7:318).
[15] Michael Allen, Grounded in Heaven: Recentering Christian Hope and Life on God (Grand Rapids, MI: Eerdmans, 2018), 82.
[16] Augustine writes: “…the will of the Father and the Son is one, and their works indivisible. In like manner, then, let him understand the incarnation and nativity of the Virgin, wherein the Son is understood as sent, to have been wrought by one and the same operation of the Father and the Son indivisibly; the Holy Spirit certainly not being thence excluded, of whom it is expressly said, ‘she was found with child by the Holy Ghost’.” In Augustine, On The Holy Trinity, ed. Philip Schaff, NPNF (Grand Rapids, MI: Eerdmans, 1956), II.v.9 (NPNF 3:41). Cf. Allen, Grounded in Heaven, 78.
[17] Fred Sanders, “What Trinitarian Theology Is for: Placing the Doctrine of the Trinity in Christian Theology and Life”, in Advancing Trinitarian Theology: Explorations in Constructive Dogmatics, ed. Oliver Crisp and Fred Sanders (Grand Rapids, MI: Zondervan, 2014), 27.
[18] Fred Sanders, The Image of the Immanent Trinity: Rahner’s Rule and the Theological Interpretation of Scripture, Issues in Systematic Theology 12 (New York, NY: Peter Lang, 2005), 38. Italics mine.
[19] “The ‘economic’ Trinity is the ‘immanent’ Trinity and the ‘immanent’ Trinity is the ‘economic’ Trinity.” See Karl Rahner, The Trinity, trans. Joseph Donceel, Milestones in Catholic Theology (New York, NY: Crossroad Publishing, 1997), 22.
[20] There is not sufficient scope in this article to develop Thomas’ concept of mixed relations. However, following him, we should clarify the word “real” here involves “no real relation in God to the creature; whereas in creatures there is a real relation to God; because creatures are contained under the divine order, and their very nature entails dependence on God”. Aquinas, Summa theologiae, Ia.28 ad 1.
[21] Hans Boersma deems this “sacramental ontology”, in Scripture as Real Presence: Sacramental Exegesis in the Early Church (Grand Rapids, MI: Baker Academic, 2017), 12. Cf. Augustine, On Christian Doctrine, trans. J. F. Shaw, NPNF (Grand Rapids, MI: Eerdmans, 1973), II.i–ii.1–3 (NPNF 2:535–536). 
[22] Sanders calls it an “economy of divine self-revelation”, in The Triune God, 72. 
[23] For instance, says Sanders, the fact that Jesus had, say, brown eyes does not indicate a “before the foundation of the world” feature. See Sanders, “What Trinitarian Theology Is For”, 30.
[24] Aquinas, Summa theologiae, Ia.3 ad 4.
[25] See Katherin A. Rogers, Perfect Being Theology, Reason and Religion (Edinburgh: Edinburgh University Press, 2000), 14.
[26] R. Michael Allen, The Christ’s Faith: A Dogmatic Account (London: T&T Clark, 2012), 115.
[27] Colin E. Gunton, Act and Being: Towards a Theology of the Divine Attributes (London: SCM Press, 2002), 69-71.
[28] See, e.g. Moltmann, who writes: “Aristotle’s God cannot love; he can only be loved by all non-divine beings by virtue of his perfection and beauty, and in this way draw them to him. The ‘unmoved Mover’ is a ‘loveless Beloved’.” Jürgen Moltmann, The Crucified God, trans. R. A. Wilson and John Bowden (London: SCM, 1974), 222.
[29] “Those who use the genetic fallacy attempt to reduce the significance of an idea, person, practice, or institution merely to an account of its origins or genesis, thereby overlooking the development, regression, or difference to be found in it in the present situation.” See T. Edward Damer, Attacking Faulty Reasoning: A Practical Guide to Fallacy-Free Arguments (Belmont, CA: Cengage Learning, 2009), 93.
[30] James Dolezal characterises Classical Theism as “deeply devoted to the absoluteness of God with respect to His existence, essence, and activity. Nothing in God’s being is derived or caused to be. There is nothing behind him or outside Him that could increase, alter, or augment His infinite fullness of being and felicity.” In James E. Dolezal, All That Is in God: Evangelical Theology and the Challenge of Classical Christian Theism (Grand Rapids, MI: Reformation Heritage Books, 2017), 10.
[31] See, e.g. Craig A. Carter, Interpreting Scripture with the Great Tradition: Recovering the Genius of Premodern Exegesis (Grand Rapids, MI: Baker Academic, 2018), 62.
[32] “Theological metaphysics” is a term from Carter in Interpreting Scripture with the Great Tradition, 63. He defines it as: “the account of the ontological nature of reality that emerges from the theological descriptions of God and the world found in the Bible”.
[33] Matthew Levering, Scripture and Metaphysics: Aquinas and the Renewal of Trinitarian Theology, Challenges in Contemporary Theology (Malden, MA: Blackwell, 2004), 36. Emphasis original.
[34] Francis Turretin, Institutes of Elenctic Theology, ed. James T. Dennison, trans. George Musgrave Giger; 3 vols. (Phillipsburg, NJ: P&R, 1992), III.xii.2 (Giger 1:207).
[35] Aquinas, Summa theologiae, Ia.1.3 ad 1.
[36] This is John Webster’s argument in “Principles of Systematic Theology”, IJST 11, no. 1 (2009): 59.
[37] For a summary of the analogia entis, see David Bentley Hart, The Beauty of the Infinite: The Aesthetics of Christian Truth (Grand Rapids, MI: Eerdmans, 2003), 242.
[38] Webster writes how the “construction of theological system is an activity with this unfinished history” and therefore cannot be exhaustively deduced by creatures who are not present to all reality. See Webster, “Principles of Systematic Theology”, 67.
[39] Thomas G. Weinandy, Does God Suffer? (Notre Dame, IN: University of Notre Dame, 2000), 33.
[40] Karl Barth, Church Dogmatics, ed. Geoffrey William Bromiley and Thomas F. Torrance, (London: T&T Clark International, 2004), §12.2, (I.1:473). 
[41] Ibid., §12.2, (I.1:473).
[42] Herman Bavinck, Reformed Dogmatics, ed. John Bolt, trans. John Vriend; 4 vols. (Grand Rapids, MI: Baker Academic, 2003), 2:313.
[43] Gregory of Nazianzen, “The Third Theological Oration”, Oration XXIX.iii (NPNF 7:302).
[44] For a valuable discussion on the term “eternal life” (ζωὴν αἰώνιον), which only appears in the same form as John 5 in Dan 12:2 (LXX), see Stefanos Mihalios, The Danielic Eschatological Hour in the Johannine Literature, LNTS 436 (London: T&T Clark, 2011), 95, 109.
[45] For a helpful discussion about divine receiving as opposed to creaturely receiving, see Holmes, The Holy Spirit, 95–96.
[46] Robert L. Reymond, A New Systematic Theology of the Christian Faith (Nashville, TN: Thomas Nelson, 1998), 325.
[47] Thomas Aquinas, Commentary on the Gospel of John: Chapters 13-21, ed. Daniel A. Keating and Matthew Levering, trans. Fabian R. Larcher and James A. Weisheipl (Washington, DC: Catholic University of America Press, 2010), §2115, 146.
[48] The Latin term res means the “actual” or “real” thing. See Richard A. Muller, Dictionary of Latin and Greek Theological Terms: Drawn Principally from Protestant Scholastic Theology (Grand Rapids, MI: Baker Books, 2006), 264.
[49] Cf. Gregory W. Lee, “The Spirit’s Self Testimony: Pneumatology in Basil of Caesarea and Augustine of Hippo”, in Spirit of God: Christian Renewal in the Community of Faith, ed. Jeffrey W. Barbeau and Beth Felker Jones, Wheaton Theology Conference Series (Downers Grove, IL: IVP, 2015), 39.
[50] See Anselm, “On the Procession of the Holy Spirit”, 393.
[51] Weinandy writes: “A proper understanding of the Trinity can only be obtained if all three persons, logically and ontologically, spring forth in one simultaneous, nonsequential, eternal act in which each person of the Trinity subsistently defines, and equally is subsistently defined by, the other persons.” Accordingly, “it is by the Spirit that the Father substantiates or ‘persons’ himself as Father because it is by the Spirit that he begets the Son.” See Thomas Weinandy The Father’s Spirit of Sonship: Reconceiving the Trinity (Edinburgh: T&T Clark, 1995), 14-15, 73. For a comprehensive critique of Weinandy’s approach, see Matthew Levering, Engaging the Doctrine of the Holy Spirit: Love and Gift in the Trinity and the Church (Grand Rapids, MI: Baker Academic, 2016), 16-22.
[52] Likewise, Anselm reasons that because God has no parts, the “whole God is from the whole God, in Anselm, “On the Procession of the Holy Spirit,” 396.
[53] Anselm, “On the Procession of the Holy Spirit,” 396.
[54] Ibid., 398.
[55] See generally Aquinas, Summa Theologiae, Ia.28.
[56] Aquinas, Summa Theologiae, Ia.28 ad 4.
[57] Augustine, as quoted in, J. N. D. Kelly, Early Christian Doctrines, 5th ed. (London: A&C Black, 1985), 275.
[58] See generally Aquinas, Summa theologiae, 1a.36.2.
[59] E.g. John 16:7; 20:22.
[60] E.g. Gal 4:6, Rom 8:9.
[61] E.g. John 16:14-15.
[62] Aquinas, Commentary on the Gospel of John: Chapters 13-21, §2105, 144.
[63] Lee Gatiss highlights the examples of Lombard in Sentences 1.15.3. Lombard himself attributes this to Ambrose and Augustine. Similarly, Gatiss explores how this use of Isa 48:16 was employed by John Gill and Augustus Toplady in arguments about the Spirit’s role in the pactum salutis. See, Lee Gatiss, The True Profession of the Gospel (The Latimer Trust, 2010), 71, fn. 103.
[64] John Oswalt, The Book of Isaiah, Chapters 40-66, 2 vols., NICOT (Grand Rapids, MI: Eerdmans, 1998), 274.
[65] See Lombard, Sentences 1.15.3.
[66] Richard A. Muller, Post-Reformation Reformed Dogmatics: The Rise and Development of Reformed Orthodoxy, Ca. 1520 to Ca. 1725; 4 vols. (Grand Rapids, MI: Baker Academics, 2003), 4.373-76.
[67] John Calvin, The Gospel According to St. John 11-21 and The First Epistle of John, ed. David W. Torrance and Thomas Forsyth Torrance, trans. T. H. L. Parker (Edinburgh: Saint Andrew Press, 1972), 110. Emphasis mine.
[68] Calvin, The Gospel According to St. John, 110.
[69] Christopher Seitz, “The Trinity in the Old Testament”, in The Oxford Handbook of the Trinity, ed. Gilles Emery and Matthew Levering (Oxford: Oxford University Press, 2011), 37-38.
[70] E.g. Neh 9:20, Isa 42:1, Ezek 36:27.
[71] Augustine, “Answer to Maximus the Arian”, in Arianism and Other Heresies, ed. John E. Rotelle, trans. Roland J. Teske, The Works of Saint Augustine: A Translation for the 21st Century (Brooklyn, NY: New City Press, 1990), II.xiv (280-287).
[72] Köstenberger and Swain put it like this: “One can be sent in time only by someone from whom one eternally proceeds.” In Andreas J. Köstenberger and Scott R. Swain, Father, Son, and Spirit: The Trinity and John’s Gospel, NSBT 24 (Downers Grove, IL: IVP, 2008), 180.
[73] An accusation made by Sergius Bulgakov, in The Comforter, trans. Boris Jakim (Grand Rapids, MI: Eerdmans, 2004), 124-127. He argues that the spiration of the Holy Spirit from the Father and the Son by the so-called one principle (una spiratione) actually distorts the Trinity in favour of two dyads: the Father – Son dyad, and the Father-and-Son – Holy Spirit dyad. For him, this contradicts the godhead because the Filioque forces “two principles” into the act of spiration, undermining the person of the Holy Spirit, who appears passive, and abrogating the monarchy of the Father.
[74] That is, “relation in God is not as an accident in a subject, but is the divine essence itself; and so it is subsistent, for the divine essence is subsistence […] a divine person signifies a relation as subsisting… And this is to signify relation by way of a substance, which is hypostasis subsisting in the divine nature.” See Aquinas, Summa theologia, Ia.29 ad 4.
[75] See Levering, Engaging the Doctrine of the Holy Spirit, 155.
[76] Levering, Engaging the Doctrine of the Holy Spirit, 155.
[77] Levering, Engaging the Doctrine of the Holy Spirit, 161.
[78] There is nevertheless what Michael Allen calls a “sequence” to Christian Theology, which is in line with biblical revelation. He argues that systematic theology follows the order of the Canon. See Michael Allen, “Knowledge of God”, 26.
[79] Webster, “Principles of Systematic Theology”, 66.
[80] Bavinck, Reformed Dogmatics, 2:258.
[81] Historically, Bavinck traces denials of the unity in order to preserve Threeness to Arianism, and formulations of unity that fail to maintain threeness to Sabellianism. See Bavinck, Reformed Dogmatics, 2:258.
[82] See generally Zizioulas, Being as Communion, 27-65.
[83] See Jürgen Moltmann, The Trinity and the Kingdom: The Doctrine of God, trans. Margaret Kohl (London: SCM Press, 1981), 198-199.
[84] See especially Miroslav Volf, “The Trinity Is Our Social Program: The Doctrine of the Trinity and the Shape of Social Engagement”, in The Doctrine of God and Theological Ethics, ed. Alan Torrance and Michael Banner (London: T&T Clark, 2006), 105-24.
[85] See generally Colin E. Gunton, The Promise of Trinitarian Theology (Edinburgh: T&T Clark, 1991).
[86] See Wolfhart Pannenberg, Systematic Theology, trans. G. W. Bromiley; 3 vols. (Edinburgh: T&T Clark, 1991), 1:319-327.
[87] Modern proponents of the Social model of the Trinity frequently cite the Cappadocian Fathers as the source of their relational ontology. Yet Stephen Holmes has convincingly shown that their readings of the Cappadocians is dubious to say the least. See generally Stephen R. Holmes, “Three Versus One? Some Problems of Social Trinitarianism”, JRT 3 (2009): 77-89.
[88] See Gunton, The Promise of Trinitarian Theology, 170.
[89] Moltmann, The Trinity and the Kingdom, 174-175.
[90] Karen Kilby, “Perichoresis and Projection: Problems with Social Doctrines of the Trinity”, New Blackfriars 81, no. 956 (2000): 433.
[91] Ibid., 441.
[92] See, e.g. Pannenberg who writes of “living realizations of separate centers of action” among Father, Son, and Spirit, in Systematic Theology, 1:319.
[93] Charles Taylor, A Secular Age (Cambridge, MA: Belknap Press of Harvard University Press, 2007), 543.
[94] See Drayton C. Benner, “Augustine and Karl Rahner on the Relationship between the Immanent Trinity and the Economic Trinity”, IJST 9, no. 1 (2007): 30.
[95] See especially James K. A. Smith, You Are What You Love: The Spiritual Power of Habit (Grand Rapids, MI: Brazos Press, 2016), 1-26; James K. A. Smith, Desiring the Kingdom: Worship, Worldview, and Cultural Formation (Grand Rapids, MI: Baker Academic, 2009), 46-47.
[96] Allen writes of the glory of the gospel – “central to its promise… is the pledge that the invisible God makes himself visible to us”, in Grounded in Heaven, 87. The particular nature of this sight is not within the bounds of this article.
[97] Muller writes: “The doctrine of God found in Reformed thought during the era of orthodoxy (ca. 1565-1725) has occupied a central place in the criticism of post-Reformation theology and has, typically, distinguished from the doctrine of the Reformers on the basis of its scholastic and Aristotelean content. Despite this reasonably prominent critique, the doctrine itself has been little studied… [and the critiques] have judged the views of the older dogmaticians on the basis of twentieth-century dogmatic constructs, and have resorted to rather vague claims: the doctrine of the orthodox writers was “rigid”, “arid”, “abstract”, characterised by “scholasticism”, and “Aristotelianism”. In Muller, Post-Reformation Reformed Dogmatics, 3:21.
[98] John Webster, “Life in and of Himself: Reflections on God’s Aseity”, in Engaging the Doctrine of God: Contemporary Protestant Perspectives, ed. Bruce L. McCormack (Grand Rapids, MI: Baker Academic, 2008), 117.