Scottish Journal of Theology

Research Article

‘Another Puzzle is . . . the Holy Spirit’: De Trinitate as Augustine's Pneumatology

Najeeb Awada1

a1 Seminar Hermannsburg Mission, Missionsstr 3-5, 29320 Hermannsburg, Germany


In their study of Augustine's De Trinitate, scholars read the fifteen books which comprise this text as a monolithically written discourse on the doctrine of the Trinity. This article is an attempt to examine if it is possible to argue on tenable bases that pneumatology, rather than any other doctrine, is the subject of Augustine's text by showing that the interpretation of the identity and consubstantiality of the Spirit occupies in De Trinitate a more foundational and central place than just being part of Augustine's discussion on the doctrine of the Trinity. It ultimately suggests that freeing Augustine's text from diachronic prejudices means also wondering if he really wanted to write an additional version of the orthodox doctrine of the Trinity which he already followed, or whether he wanted to contribute something new about a relatively neglected doctrine in the faith of the church.


In a letter to Bishop Aurelius of Carthage, which he wrote to introduce the collection of books called De Trinitate, Augustine states that, despite being written separately, these books’ inquiry ‘proceeds in a closely-knit development from the first of them to the last’.1 In their study of Augustine's De Trinitate, scholars keep Augustine's words in mind and read the fifteen books which comprise this treatise as a monolithically written discourse. De Trinitate is, thus, read either as the wellspring of the ‘western essentialist’ interpretation of the credal doctrine of the Trinity,2 as a defence of christology against Arianism,3 as metaphysical elaboration on the divine trinitarian Being of God,4 as one of the earliest patristic writings which introduces the Filioque to western trinitarian theology5 or even as a Latin discourse on the monarchy of the Father as the principium of the Trinity.6

Is it possible that what makes the books of De Trinitate a closely knit treatise is a theme other than any of the above-mentioned ones? More specifically, what if Augustine's first and foremost purpose in De Trinitate is to present an intelligent, original explanation of the identity of the Holy Spirit? This article is an attempt to examine if it is possible to argue on tenable bases that pneumatology, rather than any other theme, occupies in De Trinitate a position more foundational and central than just being part of Augustine's discussion on the Filioque, christology or even the doctrine of the Trinity. The article, nevertheless, is not an assessment of the content of Augustine's thinking on the Holy Spirit, and it neither aims at defending nor challenging how he interprets the Spirit's relation to the Father and the Son. Also, this article is not a comprehensive commentary on the pneumatology which runs through all the fifteen books of De Trinitate. It is rather an attempt at exploring the tenability of considering pneumatology, rather than any other teaching, as the overarching theme of De Trinitate, and of rereading this text from this specific angle.

The Two Puzzles of De Trinitate

In book 1, chapter 1 of De Trinitate, Augustine states the main theme he attempts to address in these books. Many, Augustine claims, have gone astray and gazed wrongly at the reality of God. Some of them, he explains, impose on God the spiritual their ideas on the bodily and the corporeal. Others ascribe to God nature and modes inherent to human spirit. Yet others transcendentalise God beyond the created universe by imposing on his reality their own speculative presumptuous views.7 For these speculators, who themselves are unable to grasp what they say, Augustine decides to develop a discourse basically showing that faith becomes understandable and speakable if we interpret it on the basis of scripture and orthodox doctrines.

The question which is more crucial than the primal context of Augustine's text, nevertheless, is what specific questions Augustine tackles to achieve the above-mentioned purpose. Augustine answers this question by setting before us two particular puzzles about which people around him ask exclusively. The first puzzle Augustine aims at investigating is the unity of the three divine agents of salvation: how can we make sense of the belief that the Father, Son and Spirit are of one and the same substance in an indivisible equality: not three gods, but one God?8 Very few scholars, I believe, would disagree that the question of the unity of the Trinity is a major issue that Augustine confronts. To say the least, there is a scholarly consensus that books 1–4 are Augustine's response to Arianism by emphasising the equality of the three persons of the Trinity. What may trigger a new discussion, however, is what I believe to be the second, and even more central, puzzle about which Augustine wrote all the books of De Trinitate. Augustine declares this overarching puzzle in chapter 2 of book 1. There, and after elaborating on what puzzles people about the unity of the Trinity, Augustine states the following:

another puzzle [which worries people] is in what manner the Holy Spirit is in the three, being begotten neither by Father nor Son nor both of them, while being the Spirit both of the Father and the Son.9

In these words, Augustine tells us that the second concern he focuses on, in relation to his belief in the necessity of explaining the unity and equality of the Trinity, is primarily about the Holy Spirit's place within the Trinity. But why does he focus on the Spirit's and not the Son's, or the Father's, relations in the Trinity? Augustine admits that the inquiry about the Son's consubstantiality needs further investigation after Nicaea and Constantinople. He is aware that the Arian challenge to this consubstantiality is still haunting the churches of his day. However, Augustine focuses on the Holy Spirit because he believes that other orthodox fathers have already confronted the question of the Son's equal divinity and given answers he totally agreed with and confessed as the catholic faith of the church.10 One can notice, from a careful reading of Augustine's elaboration on the Son's consubstantiality, its lack of noteworthy originality and its loyal echoing of conventional christological and trinitarian claims made by other fourth-century Fathers (e.g. the Cappadocians and Athanasius) – and this eventually encourages the endeavour of tracing Augustine's thinking back to these Fathers’ writings.11 But one can validly argue that originality in relation to christology does not busy Augustine, since he explicitly states that he is building upon the originality of the christological and trinitarian discourses of the catholic commentators before him.12

It is undeniable that Augustine dedicates entire books to speaking about the Son's equality with the Father and their homoousian unity. His argument on books 4–6, for instance, looks totally christological in form. His defence of the Son's consubstantiality, which is traditionally an item in the discourse on the Trinity at least up until the fifth century, gives the impression that the books mentioned are pertinent to a sole concern of offering a comprehensive interpretation of the Trinity and the divine triune ontology. Assuming this framework right from the outset, however, prevents one from noticing that arguing for the equality of the Father and the Son also, in fact, serves well Augustine's investigation of the puzzle of the identity of the Holy Spirit. From the first book of De Trinitate, Augustine departs from a claim that the Spirit is ‘both of the Father and the Son’.13 He is the gift of both; their love to each other and to us. They together spirited the Spirit and sent him to us. Ostensibly, the emphasis on togetherness is uncongenial with the monarchical particularity of the Father from the angle of the doctrine of the Trinity. This togetherness, nonetheless, serves well another attempt at showing the real, equal divinity of the Holy Spirit specifically from the consubstantiality and unity of the other two divine persons of the Godhead, which as such is the first puzzle Augustine keeps an eye on in De Trinitate.

More interesting here is Augustine's speech, almost through all the books of the treatise, on the Spirit as the gift of the Father and the Son who is co-sent by them. The language of ‘giver-gift’ or ‘sender-sent’ makes much sense in relation to Augustine's tackling of a pneumatological puzzle. In order to establish his argument for the consubstantiality of the divine gift on a solid theological hermeneutics of unity in the divine Godhead, Augustine resorts to an orthodox affirmation that the Son is homoousios with the Father. However, he uses this affirmation for a purpose different from the soteriological, ontological or incarnational ones which we detect in the writings of fourth-century Fathers. For him, nothing can show the consubstantiality and equality between the divine gift (Spirit) and its givers other than the equality and the consubstantiality which combines and unites the two givers together: if those who give the Spirit together are equally God, the gift they offer is like them, divine and consubstantial. If, on the other hand, one of the givers is less divine or not really God (i.e. the Son in this case), this will not only abolish the divine unity in the Godhead, it will, more crucially, deny the foundation of the evidence for the Spirit's consubstantiality. This logic lies behind Augustine's belief that the Son shares with the Father the same actions when he states:

If some things were made through the Father, others through the Son, then it cannot be all things through the Father nor all through the Son. But if it is all things through the Father and all through the Son, then it is the same things through the Father as through the Son.14

These words are not said here to articulate the inseparability of the three divine persons to confront any charge against the orthodox doctrine of the Trinity with tritheism. Stressing inseparability serves here the purpose of showing the equality between the Father and the Son (attending the first puzzle), while equality, in turn, serves in proving the consubstantiality of the Spirit with his senders. This can be extracted from Augustine's move in chapter 2 of book 1 from speaking about the consubstantiality of the Father and the Son in paragraph four into speaking about the Spirit, and not the Trinity or the Son, in the following paragraphs, and consequentially concluding that:

the Holy Spirit . . . too is God and not a creature. And, if He is not a creature, then He is not only God . . . but also true God; therefore absolutely equal to the Father and the Son, and consubstantial and co-eternal in the oneness of the three.15

In book 2 of De Trinitate, Augustine elaborates further on the consubstantiality of the Spirit by exploring more the act of sending and the ‘sender-sent’ relationship. He principally argues that the Father's sending of the Son neither makes the sent Son substantially subordinate to the Father in essence, nor does it state that between the two senders of the Spirit there is one (i.e. the Son) who is not really God from God, just as it does not imply the inequality of the Spirit to the Father and the Son. The very act of sending as such is possible because of the unity of the sender and the sent. This is the case in the sending of the Son as well as of the Spirit. In eternity, the two senders are both conducting the act of sending.16 The roles of ‘sender’ and ‘sent’ are just expressions of the dynamic nature of the unity and the infinite consubstantiality of the three persons. And what applies to the Father and the Son with this regard applies also to the Holy Spirit and makes it ‘easy to understand’, as Augustine states, ‘how the Holy Spirit can also be said to have been sent’.17 Up to book 4 at least, Augustine continues that same argument-strategy of showing the consubstantiality of the Father and the Son (as senders) in order to prove thereupon the Spirit's consubstantiality with the Father and the Son, which is not to be negated by the fact that the Spirit is their gift and the love which combines them eternally.18

Reading De Trinitate from the Puzzle of the Spirit19

In the light of the previous discussion, Augustine's twofold task in De Trinitate is, first, about the unity and consubstantiality of the three divine persons despite the (biblical and doctrinal) emphasis on their particularity in terms of role and subsistence.20 Yet more centrally still, Augustine presents, second, an extensive interpretation of the role and identity of the Holy Spirit, aiming at giving as much attention to the Spirit as the attention which the catholic faith grants to the Father and the Son. This attention to pneumatology is generated from a conviction Augustine uncovers in some of his other writings, namely, that the identity of the Spirit has not yet been sufficiently understood in the West at his age. In as early a text as his De Fide et Symbolo, for example, Augustine states:

And, indeed, on this subject of the Father and the Son, learned and spiritual men have conducted discussions in many books . . . with respect to the Holy Spirit, however, there has not been as yet, on the part of the learned and distinguished investigators of the scriptures, a discussion of the subject full enough or careful enough to make it possible for us to obtain an intelligent conception of what also constitutes His special individuality (proprium) . . .21

Here also, Augustine establishes his view of the Spirit in an emphasis on the unity and consubstantiality of the three divine persons. And he reveals his belief that the best language to express the equal divinity of the Spirit is one which speaks about the Spirit as the relation of love between the Father and the Son, rendering this relationship role constitutive of the Holy Spirit's identity because it proves his divinity.22

In De Trinitate, Augustine develops the intelligent conception of the identity of the Spirit he believes is missing from the teaching of the church. This time, he takes the understanding of the unity of the Trinity a pneumatological step further by replacing the traditional ‘essence-hypostasis’ axiom of the doctrine of the Trinity with an ‘essence-characteristic’ axiom, because this latter seems to be for him more convenient to the puzzle of the Spirit. Upon this axiom, Augustine considers ‘persons’ expressive of ‘energies’ and assumes the total identification of the divine essence and its energies. ‘Energies’ here invoke a functional connotation, for the energies do not reflect the divine essence. They are this essence relationally and functionally disclosed: the Father, the Son and the Spirit are the disclosure of the Godhead in its infinite oneness. Be that as it may, the relationships of the three persons (biblically spoken about in ‘sender-sent’, ‘giver-gift’ language) are the divine Godhead per se. And it would be deemed more congenial from this perspective to speak about the Godhead's unity as one of a society of relationships named ‘Father, Son and Spirit’; not, that is, as a koinonia of three hypostases. This is compatible with Augustine's belief that what God is is how God exists.23 And it makes natural his speech about the three persons and their consubstantiality as a reflection of the relational life of God's oneness, rather than of the trinitarian particularity in the Godhead. This is why in Augustine's trinitarian language there is a dominating emphasis that God does not have three essences, therefore God is not three persons, but three relations which are signified by the names, ‘Father, Son and Spirit’.24 It is this framework which forms the boundaries of Augustine's speech about the Spirit as the ‘gift’ of the Father and the Son, not as a person with them,25 and his defining of the Spirit as a relationship of love in the Godhead.

Augustine's definition of the Trinity as fellowship of love starts with an explanation of the possibility of understanding the Trinity rationally by means of a language relevant to human existence.26 Augustine's argument in the light of this possibility runs as follows: if the Godhead is the Trinity, and if the Trinity names the relations between God the Father and God the Son and if, finally, God is love as 1 John 4:1627 states – which concurs with the primary claim that God's existence is who God is – then love as such connotes relations and the relations of love are the Godhead in its substantial unity. The question here is: why does Augustine speak about a love relationship between two and not three? The reason is his understanding of love as a relationship of dual, not triangular, nature.28 And also his belief that identities cannot be reciprocated like attributes: there must be only one loving Father and one beloved Son. Be that as it may, the Spirit can neither be ‘lover’ nor ‘beloved’, since these are restricted to the Father and the Son. The only place left for the Spirit in the Trinity is the relation between the lover and the beloved. This is better than removing the Spirit out of the Godhead and failing to show his consubstantiality.

By making the Spirit a relationship of love between the Father and the Son, Augustine achieves his goal of showing that the Spirit is not an accidental action the Father and the Son make for our sake in history. He is a substantial reality which is co-constitutive of the Godhead in its eternity because as love the Holy Spirit is the supreme charity which unites the Father and the Son as well as the foundation of their consubstantiality.29 For Augustine, this does not reduce the Trinity to a two-fold character. It rather founds the Trinity on a balanced form of relationality, because (1) it reflects a triad of lover, beloved and love and (2) because love designates the three persons’ essence as together one God (since God per se is love), without this denying the Spirit's particularity as alone being called ‘love relationship’ in the Trinity.30 The Holy Spirit's consubstantiality and divine identity lies, for Augustine, in being a subsisted, substantial qualification for those who co-send and reciprocate him between them.

Pneumatological Perception of Terminology

The concern about the Spirit's consubstantiality explains why Augustine would opt for speaking about three names rather than three persons as the Trinity and would elect this non-personal terminology to describe the Spirit.31

In De Trinitate, Augustine sets before his readers the core of his preference to speak about ‘Father, Son and Spirit’ as three names for one persona with one essence. This choice lies in his distinction between ‘specific names’ and ‘generic names’. By the first, Augustine means names which identify the common substance of various things. And by the second he means names which identify things which are different in substance, yet share common characteristics. ‘Father, Son and Spirit’, Augustine argues, are not generic names because they do not present three different substances or essences. They, thus, are specific names and not persons. If generic names are designative of things which are not only numerically but also substantially different, and if there is no difference in essence between the Father, the Son and the Holy Spirit, calling them ‘persons’, then, is not feasible unless this last term is understood generically and not specifically. But ‘person’ for Augustine cannot be a specific name because it designates a characteristic common to various separate things. Be that as it may, a generic name like ‘person’ cannot be used to name the divine three in God or to show their unity and consubstantiality.32

One may say, in the light of the above, that Augustine's naming of the Father and the Son ‘lover’ and ‘beloved’ may allow for calling them hypostases or personae; whereas this is not possible in the case of the Spirit. For the Spirit is deemed the relation of love between them, not someone who loves them or is in love with them. How can love subsist in a personal form and be a relation at the same time, or how can a relation exist alongside its agents, as if an agent as such with them? Love as a concept, as an idea, can hypothetically exist as an ideal idea in the mind, regardless of its actual incarnation in reality. But love as a relationship – as Augustine defines it –cannot subsist by itself without its related subjects. The Spirit, in other words, would not exist by virtue of his being, because as a relation he is the outcome of the Father–Son interaction. The Spirit, nevertheless, can only subsist by virtue of who he is if he is a third agent with the other two in a relational framework.33

Augustine opts for remaining silent on the Spirit's personal agency because he takes this hypostatic individuation for granted and acknowledges the way by which the catholic faith speaks about it in the doctrine of the Trinity. At a certain point, Augustine shows readiness to sacrifice the name ‘Holy Spirit’ itself, not only ‘person’, when he thinks that it does not serve the main purpose of his discussion: proving the consubstantiality and unity of the Spirit with his divine senders. This is what book 5 of De Trinitate suggests. There Augustine says the following:

whatever God is called with reference to self is both said three times over about each of the persons, Father, Son and Holy Spirit, and at the same time is said in the singular and not the plural about the Trinity.34

What does this singularity imply pneumatologically? According to Augustine's understanding of the Spirit, it pinpoints the Spirit's equality with the Father and the Son and demonstrates his individuation within the network of relations in the Godhead. The Spirit alone, Augustine concedes, is the person in the Trinity which can properly or peculiarly be called ‘Holy Spirit’.35 This said, ‘Holy Spirit’ per se does not clearly show, as Augustine realises, the consubstantiality of this particular divine person in the Godhead. To say the least, it does not show this sufficiently to Augustine's opponents, who understand by ‘person’ separate, individual substance and consider personal names designative of separate entities. Therefore, in order to show that the personal name ‘Holy Spirit’ does not negate unity, but rather stems from it, Augustine relies on another scriptural name for the Spirit: ‘the gift of God’. For Augustine, this latter name is a more appropriate expression of the unity between the Spirit and his givers. For, far from making the gift subordinate to its givers, the ‘giver-gift’ relation between the three divine persons proves their consubstantiality as single, divine Godhead. This is the backbone of Augustine's saying ‘when we say “the gift of the giver” and the “giver of the gift”, we say each with reference to the other’.36

Reading Augustine's above-mentioned discussion from a narrow concern about tracing in his books a coherent doctrine of Trinity congenial with the fourth-century trinitarian thinking may eventually lead to charging Augustine with binitarianism. By speaking, that is, about the Spirit as the common gift of the Father and the Son, Augustine may be charged with reducing the Spirit into something between two divine agents in God, which makes Augustine's view of the Trinity less trinitarian than orthodoxy allows. This notwithstanding, if one reads Augustine's terminology and his view of ‘names’ as part and parcel of a broader discussion on pneumatology, the inquiry on the particular personhood of the Spirit and the proof of the constitutive significance of this personhood for the Godhead need no more immediately occupy the centre-stage of the discussion, nor does Augustine's opinion about them, which peppers his account every now and then, need to be the core of interpreting De Trinitate.37

Pneumatologically speaking, showing that the Holy Spirit is a common reality between the Father and the Son aims at saying that unless the Spirit is one with the Father and the Son in substantial unity, he would not be their gift and they would not be his giver, and the name ‘Spirit’ would not commonly designate the three. If the main purpose here is not proving that the three in the Godhead are hypostatically equal in their influence and actions in the Godhead, but that they are consubstantial and united despite their different roles and names, then saying that the Spirit is the gift of the Father and the Son, or the love between them, serves the purpose of basing the Spirit's identity on the fact of the unity in the Trinity. From the angle of pneumatology, what counts is showing that ‘with reference to creation, Father, Son and Holy Spirit are one origin, just as they are one Creator and one Lord’.38 This claim presupposes the hypostatic nature of the triune Godhead and builds upon it the following pneumatological conclusion: though he is the gift and love which is shared by the Father and the Son, the Holy Spirit is such simply because he is the third equal, consubstantial and co-eternal hypostasis with them.

De Trinitate as De Spirito Sancto

By ending the previous discussion, I return to the first inquiry I departed from: could Augustine's De Trinitate be his book on pneumatology, first and foremost? My argument attempted to show that this is a plausible and verifiable possibility. It is tenable to say that Augustine's argument on the consubstantiality of the Father, the Son and the Spirit serves in his mind the purpose of stressing the unity of the Trinity after some of his contemporary fellows fell into the ‘many’ and disintegrated the triunity of God by means of it.39

This may, on the other hand, sort out the ‘ambiguity’40 of which some scholars accuse De Trinitate when they come to read it from a prefabricated conviction that the text is Augustine's interpretation of the doctrine of the Trinity. Scholars started to acknowledge that De Trinitate may not be Augustine's complete doctrine of the Trinity after all, but just a text which discusses things from a specific trinitarian angle. Michel René Barnes, for instance, notices Augustine's focus on the issue of unity in particular and argues that Augustine's concentration on developing an exegesis of 1 Corinthians 1:24 in books 6 and 7 aims basically at articulating what the Nicene faith does not fully articulate about the equivocality and full unity between the Father and the Son with regard to wisdom and power. Barnes goes even further in concluding accurately that ‘Augustine's trinitarian theology develops, and its most fully-developed articulations are not in De Trinitate at all’.41 Barnes's view qualifies in a useful manner the standard approach to De Trinitate which divides the text into a part which presents the orthodox faith on the Trinity (bks 1–7, 1–4 or 1–8), and another part on the proper rational understanding of this faith according to Augustine.42 This attention to Augustine's focus on the issue of unity, as well as the qualification of the standard structuring of De Trinitate from the standpoint of the doctrine of the Trinity, indicate that the first puzzle Augustine tackles in his treatise is fully recognised and seriously taken into consideration in Augustinian scholarship.

What I think still needs sufficient attention and appreciation is the centrality of the second puzzle on the Holy Spirit for delving sufficiently into the theological deep of De Trinitate. There is a need to realise that the concern of Augustine about unity is his passageway towards developing an intellectual discourse on the Holy Spirit. The incompleteness of his trinitarian thinking is due to the fact that the bishop of Hippo made a big pneumatological turn from the track of trinitarian unity. Regardless as to whether the standard division of the books of De Trinitate still stands as is or needs qualification,43 I propose the following twofold purpose as the one which combines the books of De Trinitate: (1) presenting a belief in the unity of the three persons as inherent to orthodox faith and (2) using this belief for interpreting intelligently the identity of Spirit.

This twofold proposal would free Augustine and his treatise from the modern criticism which narrowly judges De Trinitate as evidence of Augustine's pioneering subjection of ‘person’ and personalism in trinitarian orthodoxy to nature and essentialism in Latin thinking. Rather than just criticising the reduction of Augustine's trinitarian thought by means of the ‘essentialist west versus personalist east’ criterion known scholarly as the ‘de Régnon paradigm’ – which seems to be a valid task to do – I propose a whole new reading of De Trinitate as basically a text on pneumatology, by freeing it from a ready-made conviction about the content which is determined by its title (i.e. On the Trinity). This is not to mean that one can really understand Augustine's pneumatology apart from his discussion of the relational dynamic of the life of the Trinity. I suggest, instead, that freeing Augustine's text from diachronic prejudices means also wondering if he really wants to write an additional version of the orthodox doctrine of the Trinity which he totally abides with, or he wants to contribute something new about a relatively neglected doctrine in the faith of the church.

Augustine's ‘another puzzle’ deserves more prioritisation and focus than we have been ready to bestow upon it. It represents a helpful reading of Augustine's De Trinitate without allowing this title to pre-shape our expectations and colour our appraisals of the validity of the claims of the text. It, to say the least, transforms the scholarship on this text into a broader study of pneumatology wherein Augustine pursues an extension of the fourth-century defence of the divinity of the Spirit. Augustine's De Trinitate is his trinitarian pneumatology rather than his doctrine of the Trinity, his trinitarian christology or his soteriology. It is Augustine's De Spiritu Sancto.


1 Augustine St, ‘The Trinity’, in The Works of St. Augustine: A Translation for the 21st Century, tr. Hill, Edmund OP, ed. Rotelle, John E. OSA (Hyde Park, NY: New City Press, 1991), p. 63 [Google Scholar].

2 Patristic scholars trace the roots of this reading of Augustine's De Trinitate in modern scholarship back to de Régnon's paradigmatic contrasting of Augustine's trinitarian, essentialist thinking to the orthodox, personalist one of the Eastern Fathers. For discussions on this paradigm in relation to Augustine and with regard to its value for reading De Trinitate as a discourse on the Trinity, see Behr, John, ‘Calling upon God as Father: Augustine and the Legacy of Nicaea’, in Demacopolous, George E. and Papanikolaou, Aristotle (eds), Orthodox Readings of Augustine (Crestwood, NY: St Vladimir's Seminary Press, 2008), pp. 153–66 [Google Scholar]; Behr, J., ‘Response to Ayres: The Legacies of Nicaea, East and West’, Harvard Theological Review, 100/2 (2007), pp. 145–52 [OpenURL Query Data]  [CJO Abstract]  [Google Scholar]; Henessy, Kristin, ‘An Answer to de Régnon's Accusers: Why We Should Not Speak of “His” Paradigm?’, Harvard Theological Review, 100/2 (2007), pp. 179–98 [OpenURL Query Data]  [CrossRef]  [Google Scholar]; and Barnes, Michele R., ‘De Régnon Reconsidered’, Augustinian Studies, 26/2 (1995), pp. 51–79 [OpenURL Query Data]  [Google Scholar]. Elsewhere, Michele Barnes points to scholars who, upon focusing on bks 5–7, read De Trinitate as a book on the doctrine of the Trinity and consider it the wellspring of all the trinitarian theology from the Middle Ages onwards: Barnes, M., ‘De Trinitate VI and VII: Augustine and the Limits of Nicene Orthodoxy’, Augustinian Studies, 38/1 (2007), pp. 189–202 [OpenURL Query Data]  [Google Scholar]. See also among the classical books which follow this approach: TeSelle, Eugene, Augustine the Theologian (New York: Herder & Herder, 1970) [Google Scholar]; and Hill, Edmund, The Mystery of the Trinity (London: Geoffrey Chapman, 1985) [Google Scholar].

3 Barnes, Michel R., ‘Rereading Augustine's Theology of the Trinity’, in Davis, S. T., Kendall, D. and O'Collins, G. (eds), The Trinity: An Interdisciplinary Symposium on the Trinity (Oxford: OUP, 2001), pp. 145–76 [Google Scholar], and Barnes, M. R., ‘The Arians of Book V and the Genre of De Trinitate’, Journal of Theological Studies, 44/1 (1993), pp. 185–95 [OpenURL Query Data]  [CrossRef]  [Google Scholar].

4 David Bentley Hart, ‘The Hidden and the Manifest: Metaphysics after Nicaea’, and David Bradshaw, ‘Augustine the Metaphysician’, both in Orthodox Readings of Augustine, pp. 191–226 and 227–52.

5 Daley, Brian E. SJ, ‘Revisiting the “Filioque”: Roots and Branches of an Old Debate, Part One’, Pro Ecclesia, 10/1 (2001), pp. 31–62 [OpenURL Query Data]  [Google Scholar]; Daly, B. E., ‘Revisiting the “Filioque”: Part Two: Contemporary Catholic Approaches’, Pro Ecclesia, 10/2 (2001), pp. 195–212 [OpenURL Query Data]  [Google Scholar].

6 Lewis Ayres, ‘Augustine's Pneumatology and the Metaphysics of Spirit’, in Orthodox Readings of Augustine, pp. 127–52. For a discussion of monarchy in Augustine which disagrees with Ayres’ interpretation and argues that Augustine's understanding of monarchy does not preclude equality for the sake of the Father, see Dunham, Scott A., The Trinity and Creation in Augustine: An Ecological Analysis (Albany, NY: State University of New York Press, 2008), pp. 45–56 [Google Scholar].

7 Augustine, On the Trinity, 1.1.

8 ‘With the help of the Lord our God, we shall undertake to the best of our ability to give [the readers] the reasons they clamour for, and to account for the one and only and true God being a Trinity, and for the rightness of saying, believing, understanding that the Father and the Son and the Holy Spirit are of one and the same substance or essence’, ibid., 1.1.4. Further down, Augustine continues, ‘I would wish to enter into [this task] in the sight of the Lord our God with all who read what I write, and with respect to all my writings, especially such as these where we are seeking the unity of the three, of Father and Son and Holy Spirit. For nowhere else is a mistake more dangerous, or the search more laborious, or discovery more advantageous’ (1.1.5).

9 Ibid., 1.2.8.

10 On Augustine's relation with orthodoxy and Eastern theology, see Carol Harrison, ‘De Profundis: Augustine's Reading of Orthodoxy’, in Orthodox Readings of Augustine, pp. 253–61; Louth, Andrew, ‘Love and the Trinity: Saint Augustine and the Greek Fathers’, Augustinian Studies, 33/1 (2002), pp. 1–16 [OpenURL Query Data]  [Google Scholar].

11 See e.g. Joseph T. Lienhard SJ, ‘Augustine of Hippo, Basil of Caesarea, and Gregory Nazianzen’, Orthodox Readings of Augustine, pp. 81–100.

12 Augustine, On the Trinity, 1.2.7. Augustine's concern about building upon, rather than extending or revising, the orthodox trinitarian theology invite one to consider carefully David Hart's claim that ‘in the case of Augustine there can be no doubt that, in its basic shape, his account of the order of intra-trinitarian relations is all but indistinguishable from that of the Cappadocians: the Son is begotten directly from the Father, while the Spirit proceeds from the Father through the Son’: David Bentley Hart, ‘The Hidden and the Manifest: Metaphysics after Nicaea’, Orthodox Reading of Augustine, p. 195.

13 Augustine, On the Trinity, 1.2.8.

14 Ibid., 1.2.12.

15 Ibid., 1.2.13.

16 Ibid., 2.2.9. ‘Furthermore, that form of the man who was taken on is the person or guise of the Son only, and not of the Father too. So it is that the invisible Father, together with the jointly invisible Son, is said to have sent this Son by making Him visible . . . as it is, the form of a servant was so taken on that the form of God remained immutable, and thus it is plain that what was seen in the Son was the work of the Father and Son who remain unseen, that is that the Son was sent to be visible by the invisible Father together with the invisible Son.’

17 Ibid., 2.2.10.

18 Ibid., 4.5.32. ‘For the moment, however, it has been sufficiently demonstrated, so I think, that the Son is not less than the Father just because He was sent by the Father, nor is the Holy Spirit less simply because both the Father and the Son sent Him. We should understand that these sendings are not mentioned in Scripture because of any inequality or disparity or dissimilarity of substance between the divine persons, but because of the created visible manifestation of the Son and the Holy Spirit; . . .’

19 I am indebted in some of the main points about Augustine's interpretation of the Holy Spirit in this section and the following one to my exposition in Awad, Najeeb G., God Without a Face? On the Personal Individuation of the Holy Spirit (Tübingen: Mohr Siebeck, 2011), pp. 61–9 [Google Scholar], 153–5.

20 On bk. 7, Augustine says that his goal, more specifically, is to present an interpretation of this issue that is acceptable and plausible for the ‘Latin mind’: Augustine, On the Trinity, 7.2.10.

21 Augustine, A Treatise on Faith and the Creed, in Nicene and Post-Nicene Fathers, ed. Schaff, Philip (Peabody, MA: Hendrickson, Publishers, 1995), vol. 3, 9.18–19 [Google Scholar].

22 Augustine, Treatise on Faith and the Creed, 9.19–21. The same logic is also stated in Augustine's On the Christian Doctrine, where the Holy Spirit is defined as the relationship that maintains the harmony between unity (particularly ascribed to the Father) and equality (particularly ascribed to the Son): Augustine, On Christina Doctrine, tr. Robertson, D. W. (New York: Bobbs-Merrill, 1958), 1.5 [Google Scholar].

23 Augustine, On the Trinity, 7.1.2. ‘Of course, if it is the same for God to be as to subsist, then it ought not to be said that there are three substances any more than it is said that there are three things. It is because it is the same for God to be as to be wise that we do not say three wisdoms any more than we say three beings . . . every single thing that is, after all, subsists with reference to itself. How much more God, if indeed it is proper to talk about God subsisting?’ (7.3.9).

24 For example, ibid., 7.3.9–11; 7.4.12. In his study of Augustine's trinitarian logic, David Coffey claims that Augustine derived this understanding of ‘persons’ as ‘relations’ from Gregory Nazianzen's saying in Oration 29.16: ‘“Father” is a term neither of essence (ousia) nor of energy (energia), but of relation (schesis), of the manner of the Father's bearing towards the Son of the Son's bearing towards the Father’: Coffey, David, Deus Trinitas: The Doctrine of the Triune God, 9 (New York: OUP, 1999), p. 68 [Google Scholar]. One should, nevertheless, be careful lest this linking makes the Nazianzen one of those who reduce hypostasis to mere relation. Coffey personally admits that the Cappadocians never took hypostasis to the extreme reductionism of ‘subsistent relations’.

25 Augustine, On the Trinity, 4.5.29; 5.3.12.

26 Something Augustine also argues for in De Civitati Dei: Augustine, The City of God, tr. Bettenson, Henry (London: Penguin Books, 1984), bk. 11 [Google Scholar].

27 Augustine, On the Trinity, 8.5.12ff.

28 Ibid., 8.5.14. ‘What is love but a kind of life coupling or trying to couple together two things, namely lover and what is being loved?’ On bk. 12, Augustine speaks about a triangular relationship of love between father, mother and child. Yet, he claims that such a relation is inconvenient for the Trinity (12.2.5). I find this logic unpersuasive. Being an imperfect image does not render the relation of ‘father, mother, child’ totally absurd. Actually, the image of ‘mind, knowledge, love’, which Augustine relies on is, by his confession, as limited and inappropriate. Add to this that the Trinity does not lie only in the notion of ‘origin’, but also in the notion of ‘love reciprocated’. Is not the triangular relation of Father, Son and Spirit a valid expression of reciprocation? Augustine does not answer.

29 Augustine, On the Trinity, 6.7; 7.6. See on this also Gioia, Luigi, The Theological Epistemology of Augustine's De Trinitate (Oxford and New York: OUP, 2008), pp. 125–46 [CrossRef]  [Google Scholar].

30 Augustine, On the Trinity, 15.2–5. In his Confessions, Augustine, along the same line of thought, calls the Spirit the gifted God alone between the Father and the Son and names him ‘the super-eminent’ love: Augustine, Confessions, tr. Boulding, Mario (New York: New City Press, 1997), bk. 13 [Google Scholar].

31 In his assessment of Augustine's trinitarian terminology, the late Colin Gunton points to this, saying that Augustine treats the Spirit ‘substantially rather than personally’: Gunton, C. E., The Promise of Trinitarian Theology (Edinburgh: T. & T. Clark, 1993), p. 37 [Google Scholar]. This, however, seems to be inevitable from the angle of Augustine's concern about proving the Spirit's divine consubstantiality rather than speaking about his trinitarian particularity in the Godhead, in the first place. For a critical conversation with Gunton's critique of Augustine's trinitarian thinking, see the recent discussion of Dunham, Trinity and Creation in Augustine, pp. 18–29.

32 Augustine, On the Trinity, 7.3.7–8. Augustine's concept of ‘name’ is derived from Plotinus’ notions of ‘quality’ and ‘substance’. Plotinus claims that the different accidents of the substance are not indicative of different qualities but of different activities which originate the substance's qualities. Plotinus also speaks about ‘differentiations of substance’ and ‘differentiations that are essential to the completion of substance’ and describes what stems from the substance as merely ‘activity’ or ‘form’: Plotinus, Enneads (Cambridge, MA: Harvard University Press, 1967) [Google Scholar], vol. 3, 2.6. Augustine, in turn, considers ‘Father, Son and Spirit’ names of three activities or relations of one God with his Word, wisdom and self. He also understands the Trinity as three substantial activities which do not change or complete the nature of the substance (i.e. are not differentiations which complete something absent in the substance), but qualitatively and distinctively disclose this substance as a relation of ‘lover’ and ‘beloved’ in God (i.e. differentiations in the substance): Augustine, On the Trinity, 11.10. See also on Augustine and Armstrong, Platonism A. H., ‘St. Augustine and Christian Platonism’, in Plotinian and Christian Studies (London: Variorum Reprint, 1979), vol. 9, p. 2 [Google Scholar]; Ayres, Lewis, ‘Giving Wings to Nicaea: Reconceiving Augustine's Earliest Trinitarian Theology’, Augustinian Studies, 38/1 (2007), pp. 21–40 [OpenURL Query Data]  [Google Scholar]; Teske, Roland J. SJ, To Know God and the Soul: Essays on the Thought of Saint Augustine (Washington, DC: Catholic University of America Press, 2008), pp. 3–69 [Google Scholar]; L. Gioia, The Theological Epistemology of Augustine's De Trinitate, pp. 47–67.

33 Thomas Marsh is correct to conclude from this specific perspective that Augustine's stress on ‘substance’ instead of ‘person’ produces an impersonal identity of God and shows that understanding the divine substance on the basis of the consubstantiality of the three persons is not fully developed in Augustine's trinitarian thinking in De Trinitate: Marsh, Thomas A., The Triune God: A Biblical, Historical and Theological Study (Dublin: Columba Press, 1994), pp. 132ff [Google Scholar].

34 Augustine, On the Trinity, 5.2.9.

35 Ibid., 5.3.12. Although the Father and the Son are also spirits, they are so, according to Augustine, not as hypostases, but as God.

36 Ibid.

37 Reading Augustine's discussion as one on pneumatology would also water down the seriousness of Basil Studer's critique of Augustine's trinitarian discourse, when Studer says: ‘Augustine himself received [from orthodoxy] this fundamental [distinction between economy and theology]. However, one can hardly maintain that he reflected properly on the methodological principles which allow us to reason from the salvific action of the Father, Son and Spirit to their eternal common life’: Studer, Basil OSB, ‘History and Faith in Augustine's De Trinitate’, Augustinian Studies, 28/1 (1997), pp. 7–50, p. 33 [OpenURL Query Data]  [Google Scholar]. This weakness in Augustine's discussion may stem from the possibility that this distinction is not one of his focal concerns in the first place. Studer points out later in his article that Augustine finds a link between economy and theology from the angle of Holy Spirit. Yet, Studer still wants to see this link as the frameworking subject and pneumatology as one of its demonstrative tools (ibid., p. 39), rather than seeing pneumatology as the framework. Had he opted for the second option, Studer would have probably found an explanation as to why Augustine does not reflect much on the relation between the temporal economy of salvation's symbolisation and the eternal reality of the Trinity (ibid., p. 50).

38 Augustine, De Trinitate, 5.3.15.

39 Thus correctly Bochet, Isabelle, ‘The Hymn of the One in Augustine's De Trinitate IV’, Augustinian Studies, 38/1 (2007), pp. 41–60 [OpenURL Query Data]  [Google Scholar]. Bochet restricts this concern to Augustine's discussion in bk. 4 (p. 46). I believe it applies to all the books of the treatise.

40 Thus Brachtendorf, Johannes, ‘“. . . Prius esse cogitare quam creder”: A Natural Understanding of “Trinity” in St. Augustine?’, Augustinian Studies, 29/2 (1998), pp. 35–45, p. 41 [OpenURL Query Data]  [Google Scholar].

41 Barnes, M. R., ‘De Trinitate VI and VII: Augustine and the Limits of Nicene Orthodoxy’, Augustinian Studies, 38/1 (2007), pp. 189–202, p. 201 [OpenURL Query Data]  [Google Scholar].

42 Cavadini, John, ‘The Structure and Intention of Augustine's De Trinitate’, Augustinian Studies, 23/1 (1992), pp. 103–23, pp. 103–4 [OpenURL Query Data]  [Google Scholar]. Cavadini reveals his reservation about the inclusiveness of this division and reminds the contemporary readers that De Trinitate is not a medieval or modern piece of dogmatic writing (p. 104). Cavadini believes that these two halves are not extrinsic to each other (p. 106). They are rather related in content and purpose (p. 110).

43 For a christological qualification of the Trinity-based division as presented by Cavadini, see Ayres, Lewis, ‘The Christological Context of Augustine's De Trinitate XIII: Toward Relocating Books VIII–XV’, Augustinian Studies, 29/1 (1998), pp. 111–39 [OpenURL Query Data]  [Google Scholar], esp. pp. 134–9.