This paper will discuss a doctrine of importance to both Augustine and Aquinas and, in the course of doing so, try to shed light on questions that come up when we discuss each one separately and the two together. All these revolve around my continuing interest in knowing and naming God. Some questions to be addressed are: is Aquinas simply in the grip of Aristotelian metaphysics in privileging “Being” over “Good” as a divine name? Does the same philosophical inclination drive him to take “He Who Is” to be a privileged name of God? Why is Christ so absent from the pages of Augustine's Confessions? And finally, does Aquinas compromise the Christian integrity of the Summa Theologiae by speaking so much about God before turning to the topic of Christ?

Aquinas is famously devoted to the doctrine of creation. Evident from the outset, this teaching grows in prominence in his two Summas and most especially the Summa Theologiae. In that work the doctrine of creation, or more properly creatio ex nihilo, subtends Thomas's account of how it is we know God and how we speak of God. It is the foundation of his famous Five Ways and, as Denys Turner has admirably demonstrated in Thomas Aquinas: a Portrait, the foundation of his understanding of free will and grace.Footnote ¹ It underlies the whole of his doctrine of God. We can see the doctrine of creation fashioning his presentation of “holy teaching” as it pronounces on “God as principal and on creatures in relation to him, who is their origin and end” (1a.1.3 ad 1). We may style this exitus/reditus strategy, but it is as recognizably the Christian doctrine of creation, from origin to end, which is the Summa's guiding principle and grounding motif.

Augustine's theology is, at first glance, less evidently centred on the doctrine of creation. Of course like all theologians of the early church he is committed to the first proposition of the Creed: “I believe in God, the Father, the Almighty, maker of heaven and earth”. It might be interesting to ask ourselves which Christian doctrine we think is most directive for Augustine? On the basis of de Trinitate, might we say that it was the Trinity or, with regard to the same work, Christian anthropology? It would be nice to say it was his Christology were references to Christ not so scant in his still most famous and widely read work, the Confessions.

Or might we better say that what most characterizes Augustine's theology is not a particular doctrine but a mode – its interiority, his sense of intimacy with the God whose face he always seeks? The language of longing, yearning and seeking is altogether characteristic of Augustine and seems the point of greatest contrast with Thomas. Two very different men writing in very different times, the one famously neo-Platonic and the other notoriously Aristotelian – or such was the story until recently.

But differences can be more apparent than real. There can be no doubt that both were God-intoxicated men, even if Thomas's published intoxication is of a more sober bent. Both understand themselves to be teachers: Augustine as a bishop and Aquinas as a Dominican, preacher and professor. Both understand Christian “teaching” to be not just the “stuff” that is taught but the practice of teaching itself. Augustine underscores this in de Doctrina Christiana and Aquinas learned the lesson. Any good exposition of Christian “doctrine” should remain always mindful of this double aspect – Christian teaching has to do with both the substance of what is taught and the activity or practice of teaching. In other words it concerns the cure of souls or, as Fainche Ryan has described it in her excellent book on Aquinas “formation in holiness”.Footnote ² Christian teaching is, for both, a matter of utmost importance as it pertains to our salvation, our growth in knowing and loving God. It is a manuduction, a leading by the hand, as was God's teaching of Israel. And this brings us to the aspect most common to both theologians, yet one so pervasive as to be almost invisible, namely, their commitment to Scripture.

Contemporary Aquinas scholarship largely concurs on three points: his Aristotelianism has been over-played, his Platonism underestimated and, most important of all from my perspective, the centrality of Holy Scripture to all he writes is insufficiently recognised. However fruitful his works have proven to be in recent years as a stalking-ground for the philosophy of religion, Aquinas was above all a theologian. In his own terms, he was a Magister in Sacra Pagina, for theology had to do with holy teaching and pre-eminently that was Scripture.

Much of Thomas's working life was taken up with commenting upon and expounding Scripture. While still assistant to Albertus Magnus, he was working on commentaries on Isaiah, Jeremiah and Lamentations. At the time of writing the Summa Contra Gentiles he was working on Job and Matthew. While in Rome as Regent-Master and composing the Prima Pars of the Summa Theologiae, he worked on Mark, Luke and John. During his second Regency in Paris (1268–1272), a period that saw him write all he would write of the Summa Theologiae before ceasing his dictation, he was commenting on Matthew and John.Footnote ³ Thomas, in short, was commenting and writing on Scripture throughout his life and this activity was not incidental to his broader projects.Footnote ⁴ Indeed while it may be natural for someone like myself, brought up to think of Aquinas as a philosopher and that it was philosophical topics that fired his interest (albeit precipitated by passing theological controversy on the nature of the soul, the eternity of the world and the freedom of the will, etc.), it is more plausible to think that he was motivated at all times by a concern to unfold, for his pupils, the radiance of revealed faith as found in the Scriptures. That, after all, had been the object of Peter Lombard's Sentences, a work that was itself an attempt to tidy up the medieval glosses. Aquinas in turn found Lombard's Sentences too baggy and chaotic to suit the needs of his students and thus he found a need for the Summa Theologiae.

So now to Scripture and creation, or better, Scripture and the metaphysics of creation. Although the Book of Genesis echoes in the creedal “Maker of Heaven and Earth”, the doctrine of creation, taken as standard and determinative by both Augustine and Aquinas, is not unequivocally to be found in the book of Genesis. Creation ex nihilo, which became a benchmark of orthodoxy by the third century C.E., seems to have been distilled by Jews and subsequently Christians from the biblical writings over the course of some centuries and especially in the period of Hellenistic Judaism. It gave answers to questions that those who composed or compiled the book of Genesis probably never asked but that Jewish monotheism, facing Greek interrogation, had to answer. Did God really make everything, and if so did he not make it from some “stuff”, even if the stuff was a primal chaos?’ “Did God make time?” (a nonsense for Aristotle). “Did the supreme deity remain aloof and delegate creation of the material world to an agent or agents?” (a notion more attractive to most middle Platonists). We strain to find explicit answers in the Bible to these questions. What is clearly attested, particularly in the Psalms and the Prophets, is that there is one God, YHWH, who made all that is and who alone is to be worshipped – points frequently made while praising the LORD'S power to save or redeem. Creatio ex nihilo emerges not so much as a branch of religious cosmology as an aspect of the doctrine of God. It tells us who this God is: the God who creates and redeems, as in:

and

The defence of divine transcendence is important in the developing doctrine – God creates all that is freely, from no compulsion – and the radical dependence of all creaturely reality upon God. A corollary of the belief that all that is comes from God and depends on God for existence is that, as Genesis tells us, all that is “is good”. The created order is precisely that – a willed and good creation of a good God, and not the product of a lesser god, or the best God could do while wrestling with a mysteriously pre-given and intransigent matter.

“Where were you when I made the stars” expresses the sort of divine transcendence and the attendant teaching that we know as creatio ex nihilo, and it is not a teaching of classical Greek philosophy. Aristotle rejected the notion as incoherent on the entirely reasonable grounds that the world must eternally be or it could not have come into being at all. Plato's demiurge moulds pre-existing matter according to the dictates of the Forms. In short, neither Plato nor Aristotle allows of a creator God. Aristotle's God is the cause of motion but not, as we shall see in both Augustine and Aquinas, the cause of being.

The first vigorous defence of radical divine transcendence, if we exclude the Hebrew Scriptures themselves, is found in the writings of a Greek-speaking Jew of the first-century C.E. writing to expound his own Scriptures. In his extensive commentaries, Philo asserts that God creates all that is and creates it out of non-existence, including matter, space and time. All things are dependent on God, but God is not dependent on anything. Commenting on Moses's encounter with God at the burning bush, and following the Greek of the Septuagint, Philo is happy to name God as “the Existent”. He also notes that God cannot technically be named since God is beyond any classification appropriate to creatures. God is beyond any genus. He says to Moses, “ego eimi ho on”, which Philo glosses as “My nature is to be, not to be spoken”.Footnote ⁵

Jews like Philo, the author of the Gospel of John, and the Christian writers who used their works, including Origen, Athanasius, Ambrose and the Cappadocians did not need pagan philosophy (and certainly not Plotinus who post-dated many of them) to bring them to the idea of God as Being itself and the source of all being. These ideas were read from their own scriptures, assisted by Greek philosophical formation, and were common coin among Christian middle-Platonists long before Plotinus and Porphyry. What was needed at their core was, minimally, a conviction that God made everything, coupled with the inclination to think through the metaphysical as well as the spiritual ramifications of this conviction. And this we find in Augustine.

If the importance of Aristotle has been overestimated in Aquinas, then the importance of Plotinus and neo-Platonism has been overestimated in Augustine. It is true that in the Confessions Augustine credits “the Platonists” with a shift in his understanding of God.

From the Platonists Augustine might have learned that the highest good transcends matter and is its source; that “all that is” emanates from the One, or the Good, in varying degrees, and that evil is not a positive substance in opposition to the good, but rather a lack. Certainly such views were vital in springing him from the trap of Manichean dualism with its denigration of the material world and exaltation of the spirit, which, by following correct practices, could float free of its carnal anchorage.Footnote ⁶ Augustine seems to have run across Victorinus's translation of the Enneads, and declares himself grateful for it, but according to John Rist there is little evidence that he had read much of it at this early stage and little evidence that what he absorbed from the Platonists bore the marks of the distinctive neo-Platonism of Plotinus.Footnote ⁷ As for the teachings that liberated him from the Manicheans, Augustine could as easily have found them in the Christian middle-Platonists of the second- and third-centuries. Augustine did not read much Greek but his mentor, Ambrose, did and knew Origen, Athanasius and Philo well. As Rist has pointed out, Ambrose himself was not evidently influenced by the “new” Platonism of Porphyry and Plotinus but by the earlier middle-Platonism which was already the “intellectual air” breathed by ancient society, pagan and Christian, by the time of Plotinus.Footnote ⁸

Nevertheless, even if he had read little of Enneads, Augustine, in the Confessions, teases his readers with allusions to this new philosophy. A famous incident is the so-called “Milan ascent” where Augustine, who has not yet embraced Christianity, describes an attempted ascent after the fashion of Plotinus.

Augustine apparently here describes a Plotinian “spiritual exercise” – seeking ecstasy by inward ascent. So overt are the Plotinian references that one philosopher of late antiquity comments, “In this passage the editions provide us with references no longer to scripture but to Plotinus abundantly”.Footnote ⁹ It may be, however, that the modern editions have just not listed all the biblical and distinctly Christian allusions that Augustine makes. The account of the experience is deeply compromised from a neo-Platonic perspective, with Christian and biblical references at every point. To start with the ascent as only “successful” because of God's assistance (“With you as my guide I entered into my innermost citadel”) and at its peak Augustine hears a voice which promises Eucharistic feeding for the passage already cited continues:

What puts the cap on it, and anchors this passage deep in what was already a received Jewish and Christian reading of Scripture, is what follows:

After this Augustine says that he could as easily have doubted he was alive than that ‘there is no truth “understood from the things that are made” (Rom.1.20).’

This is an endorsement, then, of a certain genuine knowledge of God, which, following St. Paul, is available to all through creation.Footnote ¹⁰ It is Augustine's reference to Exodus 3 and God's self-disclosure to Moses at the burning bush that I wish to pick up, reminding us that Aquinas will introduce his reply to the pivotal Summa question “Is there a God?” –with the same text:

This scriptural sed contra launches Thomas's famously brief account of the Five Ways. I wish I could say that this quotation from Exodus 3.14 “famously” launches his presentation of the Five Ways, were it not for the fact that most modern philosophical writers pay little attention to the biblical citation lodged in the sed contra. Not surprisingly so, for it can look like a gratuitous proof text:

Yet Exodus 3.14, the disclosure of the name to Moses, was for Aquinas and his contemporaries a purple passage. By Thomas's time, and indeed long before it, “I am who am” (Ego sum qui sum) was not just a biblical quotation but a name of God, and a very privileged name because it was held to be one of those rare moments of divine self-denomination recorded in Scripture and linked, by the text, to the name that Aquinas will say is the most appropriate name for God, “He who is”.

Aquinas will have known the passage in the Confessions that, in connection with the “ascent” at Milan, links Exodus 3 and Romans 1.20 to the natural knowledge of God, and Aquinas indeed cites the same two biblical texts in quick succession, here in sed contras at the beginning of the Summa: Romans 1.20 as the sed contra to 1a.2.2 and Exodus 3.14 as the sed contra to 1a.2.3. But we do not even need to think of Aquinas borrowing from Augustine here. He is as much following a received pattern of reading scripture.

Aquinas is also aware, as were Bonaventure and Dionysius, that Exodus 3.14 is, by ancient usage, a premier text when the concern is about knowing and naming God – precisely those matters he intends to discuss now. For the Five Ways, whatever the effectiveness they may have as proofs for the existence of GodFootnote ¹¹ are here used to introduce Thomas's first expansion of the doctrine God. Indeed I suggest that to focus solely on their efficacy as proofs (always somewhat unaccountable in virtue of their brevity) and to fail to see that they open up Aquinas's discussion of naming God is to get the Summa wrong from the outset. Aquinas and his intended readers did not doubt God existed but there are real questions to answer, as far as Aquinas is concerned, as to how it is we can know what God is or, more accurately in the first instance, “what manner of being he is not” (Prologue to Questions 3–11). It is under this chaste rubric that Aquinas will now discuss God's simpleness, perfection, limitlessness, unchangeableness and oneness.

Bonaventure, Aquinas's contemporary and colleague, devotes two of the middle chapters of The Soul's Journey into God to two privileged names for God and in doing so gives us a glimpse of the contemporary interest in the Names. He tells us that John Damascene “following Moses” says that “He Who Is” is God's primary name and that Dionysius the Areopagite, “following Christ” says that “the Good” is God's primary name. It is important to stress that both ‘Being’ and ‘Good’, while they appear to us to be philosophical ascriptions, were for Bonaventure and Aquinas, as for Dionysius himself, scriptural names for God. Not only so but they were names of the highest order because unlike praising titles like rock, fortress and shepherd, they were divine self-descriptions – names God was credited with giving to himself. Both Bonaventure and Aquinas were influenced by Dionysius's Divine Names, a work that enjoyed almost apostolic status in their time, since it was believed that the author was St. Paul's convert mentioned in Acts. But we would be wrong to think that Dionysius was the only formative influence for Aquinas on these questions. There was a long tradition of interest in and meditation on the divine names. Medievals were familiar with prayers and litanies invoking these names: Lamb, Watchman, Word, Light, Counsellor.Footnote ¹² These names, some from the New Testament, many from the Old Testament, had formed the basis for praise and theological reflection for Origen, Chrysostom, Hilary of Poitiers, Jerome, Ambrose and many others. The names were widely recognised to have different characters. Ambrose had divided them accordingly into three categories: figurative or symbolic names (Rock, Fortress), proper names signifying the Trinity in common (Good, One), and proper names signifying the singular persons of the Trinity (Father, Word). Other writers, such as Ephrem the Syrian, made different divisions.

Aquinas ran across the ancient theological debates on the names and their categorization early in his career while commenting on the Sentences of Peter Lombard, who discussed the divisions of the names given by Ambrose and Augustine. Aquinas was also familiar with the divisions made by John Damascene and Pseudo-Dionysius and, while still assistant to Albertus Magnus, he had written up Albert's commentary on Dionysius's Divine Names as lecture notes.

That “He Who Is” is the most fitting name of GodFootnote ¹³ had long been attested by both Latin and Greek fathers and was, furthermore, linked with the idea that God is “Being itself”. As we have seen, this connection was already made in the first-century by Philo, who understood the Septuagint's “ego eimi ho on” to be equivalent to saying that God is “Being itself”, or “the Existent One”.

While still assistant to Albertus Magnus, Aquinas found discussions of “He who is” as a privileged name for God in both Peter Lombard himself and in Albert's commentary on him. He also found a Jewish perspective in Lombard – that of Maimonides in the A Guide to the Perplexed, who said that “being” or “I am who I am” is the most appropriate name of God.Footnote ¹⁴

But where does the doctrine of creation come in? By the time he was starting to write the Summa Theologiae, Aquinas had made further detailed study of the Guide to the Perplexed and found in Maimonides a great ally on the centrality of creatio ex nihilo. Not only did Maimonides insist that this was the one teaching the three great traditions of Judaism, Christianity and Islam held in common but he is emphatic that it is not a teaching of the philosophers, even his beloved Aristotle. For Maimonides creatio ex nihilo is a high rampart around the Law of Moses. He sees it protecting many of the same convictions that we find in Aquinas: the sovereignty of God, human and divine freedom, miracles.

Even time itself is created and, like Philo, whose writings we have no reason to believe Maimonides knew, Maimonides sees that it has implications for religious language:

Maimonides’ scheme was famously so austere, as Aquinas noted with concern, that our language about God could only be equivocal; to say God is “wise” meant he was the source of wisdom in creatures, to say he was “good” the same.

Around the same time that he was immersing himself in Maimonides, Aquinas made his own careful reading of the Divine Names of Pseudo-Dionysius and we should ask why Aquinas, who had already examined this work while he was Albert's assistant, should return to make his own careful study at a later date, which he did either during his time at Orvieto when he was finishing the Summa contra gentiles, or in Rome as he began the Prima Pars of the Summa Theologiae? Torrell suggests mildly that the commentary shows the increasing influence of neo-Platonism in his work, but this is not evidently so. Aquinas in fact distances himself from many of Denys's most distinctively neo-Platonic elements. The answer may be that the growing centrality of creatio ex nihilo to his mature theology and his further immersion in Islamic philosophers as well as Maimonides, was bringing the whole question of “religious language” (divine names) to a point of crisis. Torrell suggests that Aquinas learned his apophaticism from Maimonides as derivative from the strong sense of the divine transcendence. Yet the idea, with respect to God, that our denials are more apposite than our affirmations was frequently articulated by Augustine and any number of Latin and Greek fathers. Not only the Summa Theologiae and the Summa contra Gentiles but his writing on Lombard's Sentences are prefaced, Torrell notes, by “apophatic declaration”. Aquinas simply pursues this in a more analytic fashion. For Thomas, “there is nothing to know about God except to know that which he is not”.Footnote ¹⁶

Aquinas, when preparing the Summa, found himself with two disparate and admired sources converging on the same theme – the impossibility of saying anything and knowing anything about God. If he found in Maimonides too austere an “apophaticism” then there was much in Pseudo-Dionysius to make Thomas's hair stand on end. Thomas cites Dionysius often but not always with approbation. He can scarcely differ from so revered an authority, but his explanations often so qualify what Dionysius said as to almost reverse it. Sometimes he can barely conceal his rage as when, in his discussion of divine simplicity, he address the question of whether God can enter into composition with other things (1a.3.8). It seems so, he begins placidly,

The response is one of the few places where we sense Aquinas becoming angry. Bad mistakes have been made on this point, he says, including “the really stupid thesis of David of Dinant that God was the ultimate unformed matter of things”. Aquinas goes on to clarify that what Dionysius meant is that “the godhead is archetypally and causatively the being of all things, but not substantially their being”.

To give him credit, Dionysius would not have embraced the “really stupid thesis of David of Dinant” but even his champions admit he was frequently sloppy. More charitably we could say his intentions in writing were doxological rather than strictly philosophical, but the neo-Platonism on which he drew was that of Proclus and this had worrying incompatibilities with Christian orthodoxy and was not always, in Denys, completely digested. In Proclean neo-Platonism the One, which was utterly transcendent, emanated “henads” or unities to which the divine names applied. Such a scheme deliberately reinstates, as neither Plato nor Plotinus did, a new polytheism.Footnote ¹⁷ Dionysius tried to qualify the Proclean legacy, rejecting the idea that the names apply to exalted beings and insisting that being derives from God alone, and making the names to be attributes of the one God. But there is still enough of a Proclean flavour to his Platonism to cause concern.

Let us return to the earlier reference to Bonaventure, who tells us in his Itineraria that John Damascene “following Moses” says that “He Who Is” is God's primary name and that Dionysius “following Christ” say God's primary name is “the Good”. For Bonaventure, as for Aquinas and all their contemporaries, both names have biblical warrant: “He Who is” from Exodus and “Good” from Mark 10.18 and Luke 18:19, where Jesus asks “why do you call me good? No one is good but God alone”. Bonventure does not choose between these two divine self-designations, devoting his fifth chapter to the Divine Unity through its primary name which is “Being”, and the sixth to the Blessed Trinity, whose name is “Good”’.

Aquinas, however, explicitly privileges the name revealed to Moses. He gives us three reasons for doing so: because of its meaning (as not signifying any particular form, but rather existence itself), by virtue of its universality or indeterminacy (for, citing Damascene, “In this life our minds cannot grasp what God is in himself”), and because of its tense “for it signifies being in the present and this is especially appropriate to God whose being knows neither past nor future, as Augustine says.” (1a 13.12, citing de Trinitate. V.2)

Thomas cites Augustine but he is at the same time faithful to Maimonides, who, expanding in the Guide (I. 65) on the “I Am who I Am”, explains that this name is given so that the Israelites might acquire “a true notion of the existence of God”, for it is a name derived from the Hebrew to be (hayah). The Scriptures, Maimonides believes, make it clear that “He is existent not through existence…that there is a necessarily existent thing that has never been, or ever will be, non-existent”. And he adds, after some discussion of the Tetragrammaton (the “articulated name”), that this absolute existence implies that He shall always be.Footnote ¹⁸ This is the eternal nature of the God of Moses – not a bald metaphysical token but “the one who was and is and shall always be” met by Moses and the people of Israel at Sinai.

This brings us again to creatio ex nihilo, which, it should be clear by now, is not to do with the beginning of time or the origins of the universe so much as with the recognition that “all that is” comes from God as has its being in relation to God. Here I want to qualify Oliver O'Donovan's suggestion that Aquinas “turns the face of faith in a cognitive direction” by his focus on Being, whereas Augustine turns us in a more ethical direction towards the Good. Aquinas does not turn the face of faith in a cognitive direction by privileging Being if that is to suggest that divine Being is something we can understand. Aquinas is emphatic (as is Augustine) that we cannot. We can know that God is Being itself, just as we know that God is Creator, without claiming to understand what that could mean. We know God as the source and foundation of all that is: he spoke and it came into being (Judith and the Psalms). For this reason Aquinas believes “He who Is” is a more fundamental a name than “Good”, or rather while “Good” may be fundamental insofar as it treats of God as cause, “to be” (esse) is presupposed in being a cause. “Good” is also liable to the blurring between Creator and creature that Aquinas sensed in Dionysius and indignantly rejected in David of Dinant. All things are indeed good, but they are so as creatures, not bits of the deity itself.

But does Aquinas in privileging the “He Who Is” remain faithful to Maimonides and creatio ex nihilo but thereby forego any reference to Christ? Is this metaphysical starting point not just further confirmation that the Christology of the Summa is an afterthought, appended to a super-structure of philosophical monotheism? To answer I will return to Augustine and his compromised Plotinian ascent, returning, as he writes to his innermost citadel, “with you as my guide”. The same mysterious guide addresses him at the summit of this endeavour with the “I Am who I Am” of Exodus 3.14. Elsewhere and often Augustine talks of this revelation to Moses as of the in idipsum: the Existent One, or Being Itself. But in a still more striking passage Augustine makes a further identification: the “I AM” who spoke to Moses is none other than Christ. Preaching on Psalm 121 (122) Augustine reminds us that Moses, when he asked for a name, was told I AM WHO I AM: “This is Being-Itself, the Self-same: AM WHO AM, HE WHO IS has sent me to you”. Augustine cautions his flock: “You cannot take it in, for this is too much to understand, too much to grasp. Hold on instead to what he who you cannot understand became for you. Hold onto the flesh of Christ….” (Boulding, Vol. VI, p. 18). The ‘I AM WHO I AM’ we cannot understand, but ‘who God is for us’, that we can understand. Augustine continues with an altogether important clarification of how he understands the Exodus passage, ‘Hold on to what Christ became for you, because Christ himself, even Christ, is rightly understood by this name, I AM WHO I AM, inasmuch as he is the form of God. In that nature wherein he deemed it no robbery to be God's equal (Phil.2.6), there he is Being-Itself.’ (The reference is to the Christ hymn in Philippians 2.6.)Footnote ¹⁹

Augustine makes an identification that is relatively common to the Fathers and Medieval thought, but somewhat eclipsed in modernity, between Christ and the one who summoned Moses from the burning bush.Footnote ²⁰ Christ is identified as the “I AM” from whom all things come. We are perhaps shocked, but why so? It is entirely biblical to see Christ as Creator, to see him identified as the Word through whom all things came into being (John I, echoing Genesis 1). It is, among other things, the Johannine Prologue to which Augustine alludes in his Milan ascent in describing uncreated light, for it is Christ who is the true light. In the startling “I AM” sayings of the same gospel (“before Abraham was I AM”, John 8.58) Jesus identifies himself with the eternal God.

These “I AM” sayings on the lips of Jesus in John's gospel take us back to Exodus but also to the “I AM” sayings of Deutero-Isaiah. There, in a striking sequence of divine self-designations, YHWH declares that he alone is God:

In the New Testament, the Pauline literature frequently alludes to Christ's role in creation, identifying him with the Word or Wisdom, famously so in I Corinthians:

And in Colossians:

The Epistle to the Hebrews begins by telling that

Like the Johannine Prologue, this is the language of creation.

Perhaps the most striking confirmation of this identification of Christ with the Creative Word, and with the “I AM”, comes in that most Jewish and thus least understood of the New Testament books, Revelation.Footnote ²¹ Revelation opens with a theophany:

In the resounding sequence of divine self-designations that follow, God and Christ are clearly named “Alpha and Omega” and “First and the Last”. These names are themselves interpretative glosses of the Name YHWH, whose only interpretation in the Old Testament is in Exodus 3 where a sequence of word-play expands upon the Tetragrammaton (which has the appearance of the Hebrew verb “to be”) and gives us eyeh esher eyeh, “I am and I will be” and “He who is”.Footnote ²²

The distinctive name “first and last” is not of New Testament coinage but already appears as a divine self-designation a number of times in Deutero-Isaiah:

And in Isaiah 48.12:

According to Richard Bauckham the divine self-designation, “the first and the last” in Deutero-Isaiah “encapsulates the understanding of the God of Israel as the sole Creator of all things and sovereign Lord of history, which Deutero-Isaiah so magnificently expounds and asserts polemically against the idols of Babylon”.Footnote ²³ In the Book of Revelation, the same divine self-designation it underscores the identification of Jesus Christ with the creator of all, the Holy One of Israel:

This “first and last” is the one who will redeem all things because he has created all things. Compare here the song of the living creatures in Revelation 4.8:

The twenty-four elders then praise God as Creator:

This creative and redeeming God is the “eternal” God of scripture, not a philosophical spectre but the Creator who always was, and is, and will be. This “eternal God” is not an intrusion of Aristotelian metaphysics (who would have made no sense of a God who created time) but reflects a very early strand of Jewish/Christian “high Christology”.

Augustine in his Milan ascent is taken to the light that is not the light of day (the light that shines in the darkness, John 1); he saw Being and trembled because he was not Being. He heard a divine self-designation “I AM WHO I AM”. At this stage in his journey Augustine does not, in his terms, know Christ – that name as a name of address will appear only later in the Confessions – but that nonetheless it is Christ who speaks to him is made evident by the following instruction “grow and you will feed on me”. It seems to me that Augustine, in a deliberate textual strategy, conceals the “mystery” of Christ in the early books of the Confessions. He will only know that it is Christ who has addressed him and carried him throughout his life when he can call Christ by name – or pray, which amounts to the same thing. “And now I was talking with you” (Confessions, Book IX.i.7). Christ is thus not “almost absent” from the Confessions or Augustine's early life, but everywhere present, if only one knows how to hear his voice.

I want to say something similar of the Summa Theologiae. It is not as though Aquinas labours through a number of matters in “natural theology” (an anachronism in any case) and then gets round to questions of Trinity and revelation. For Thomas and his contemporaries the I AM WHO AM is already Christ as witnessed in Paul and the Book of Revelation: the one who was, and is, and is to come. Christ is the God whose presence to us as Being Itself and the source of being is unfolded in those first, philosophical, questions of the Summa. This is made textually evident at a number of junctures, for instance in ST 3.3 when, in a sed contra to a question on divine simplicity, Aquinas tells us “God is not only called living but life: I am the way, the truth and the life”. This is a Christic self-designation that Aquinas, without pausing, takes as a name of God.

As Henk Schroot insists in Christ, the Name of God, Thomas's scriptural references are never just ornamental. Here we no doubt suffer because we do not read the Summa in conjunction with his biblical commentaries. To give just one relevant example of his exegetical practice: in his commentary on Matthew, Aquinas notices that Jesus's final words to his disciples and those with which the Gospel ends (“I am with you always, to the end of the age”, Matt.28.19) echo the announcement of the birth of Christ to Joseph in a dream. There Joseph is told by the angel of the LORD to name his child Jesus, and the texts adds, to fulfil the prophecy ‘”they shall name him Emmanuel” which means, “God is with us”’ (Matt. 1.21–23, referencing Is. 7.14). The “God with us” is the “Alpha and Omega”, the “first and the last, who is and was and is to be”. For Aquinas, as for Augustine before him, in this life it is through Christ that we travel to Christ, who is the “beginning and end of all things and of reasoning creatures especially”.Footnote ²⁴