Beyond Cyril? Martin Luther's quest for christological agency

Abstract

This article examines a long-standing association of Martin Luther's christology with that of Cyril of Alexandria. However, for all its heuristic promise, the designation ‘Cyrillian’, must in Luther's case be understood either as an overly generalised statement of a well-established grammar of christology – in which case it simply is Luther's foundation and, as such, explains nothing specific about Luther's christology and, moreover, fails to do justice to the reformer's crucial argumentative moves. Alternatively, when taken for a set of material similarities, the designation is simply inaccurate, for Luther is decidedly not a Cyrillian, despite some fundamental convergences with the thought of the Alexandrian patriarch. Luther's context, as we demonstrate, leads him not only to go beyond Cyril, but also to argue in a manner contrary to Cyril, in order to secure what for both theologians is a realist eucharistic backdrop of their commitment to the Word's incarnation.

It is not infrequent, and heuristically rather convenient, to assume that the Christology that the German reformer, Martin Luther (1483–1546), championed was, in some significant manner, Cyrillian.¹ What the following will argue is that the designation, for all its promise, must, in Luther's case, be taken either as an overly generalised statement of a long-established grammar of Christology – in which case it simply is Luther's foundation and, as such, explains nothing specific about Luther's Christology. It moreover, fails to do justice to the reformer's crucial argumentative moves. Alternatively, when taken for a set of material similarities, the designation is simply inaccurate, for Luther is decidedly not a Cyrillian, despite some fundamental convergences with the thought of the Alexandrian patriarch. Luther's context, as will be demonstrated, leads him not only to go beyond Cyril, but also to argue in a manner contrary to Cyril, in order to secure what for both theologians is a realist eucharistic backdrop of their commitment to the incarnation of the Word.

Luther as a Cyrillian?

The trope of Luther as a Cyrillian may be beholden to the significant number of quotations from Cyril's oeuvre, and the Alexandrian tradition more generally, that can be found in the writings of later sixteenth-century Lutheran theologians; they saw their appeals to this tradition as a way to buttress Luther's own teaching and carry forward his mantle. In large part, the ascription of a Cyrillian character to Luther's Christology is due, however, to how Luther's embattled polemic with the Swiss followers of the Reformation is often mapped heuristically onto the arch-conflict between the ancient patriarchs of Alexandria and Constantinople. Here Ulrich Zwingli is unenviably cast as espousing a Nestorian view of the person of Jesus Christ. Luther himself bears some responsibility for this perspective, even though it came to him as a rather belated insight. In Von den Konziliis und Kirchen (1539), Luther offers the following reflection:

I too have been confronted by Nestorians who fought me very stubbornly, saying that the divinity of Christ could not suffer. For example, Zwingli too wrote against me [in his Friendly Exposition of the Eucharist Affair, to Martin Luther (1527)] concerning the saying, ‘The Word became flesh.’ He would simply not have it that ‘became’ should apply to ‘Word’. He wanted it to read, ‘The flesh was made word’, because God could not become anything. I myself did not know at that time that this resembled the notion of Nestorius … but recognized it as error on the basis of Holy Scripture, Augustine, and the master of the Sentences. Who knows how many Nestorians may still be in the papacy, praising this council [of Ephesus] greatly and not knowing what they praise? For reason wants to be clever here and not tolerate that God should die or have any human characteristics, even though it is used to believing, like Nestorius, that Christ is God.²

Now, whether associating Zwingli's theology with Nestorianism suffices to define Luther's antagonistic position as Cyrillian is a different question – one that invites much caution. To begin with, Nestorianism, as Luther understands it, is not quite the same as the theology of Nestorius. (Just as, rather obviously, Lutheranism itself will turn out not to be exactly coterminous with the theology of Luther.) As a matter of fact, Luther may actually be the first modern theologian to raise the question of whether Nestorius actually was Nestorian.³ The reformer offers a remarkably sympathetic, though in the end rather negative, picture of Nestorius’ thought. He is incomparably harsher in his assessment of Zwingli's ‘Nestorian' views. When it comes to Nestorius, ‘although speaking logically it must follow from Nestorius’ opinion that Christ is a mere man and two persons, this was not actually his opinion’, Luther opines.⁴ Nestorius's error, as Luther sees it, lies in the patriarch's careless logic. What Nestorius sought to affirm – the unity of Christ – could not possibly follow from his premises, which were hampered by too stringent an application of ‘grammar or philosophy’ to concepts, such as ‘mother’, ‘God’ and ‘man’.⁵ Again, Luther: ‘Nestorius’ error was not that he believed Christ to be a pure man, or that he made two persons of him; on the contrary, he confesses two natures, the divine and the human, in one person – but he will not admit a communicatio idiomatum.’⁶ Nestorius, in other words, does not allow the context, the union, to temper his pre-understandings. On this basis, Luther comes to see the error of Nestorianism as fundamentally formal, or logical, in character. He identifies it more broadly, for example, in Rome's insistence on works as belonging to the order of salvation. Nestorianism comes to typify both a failure of logical procedure in syllogistic reasoning and a simultaneous, wrong-headed insistence on the self-evident character of theological language.

Luther, of course, had at best only a fragmentary and second-hand knowledge of the Nestorian controversy. It is safe to conclude he did not know Nestorius from the latter's primary writings.⁷ The same, however, though somewhat more cautiously, must be said about Luther's knowledge of Cyril of Alexandria. The library catalog of the University of Wittenberg, dating back to 1536, does list Cyril's commentary on the Gospel of John, which actually predates the outbreak of the controversy with Nestorius, but that is about how far things go.⁸ On the Councils and the Church – where Luther offers his mature account of the role of patristic and conciliar testimony in theological debate – mentions Cyril only in passing. He is merely another among a number of ‘proud bishops’; beyond this, Luther offers no theological engagement with him.⁹ By contrast, Luther's colleague, Philip Melanchthon, and especially students, Johannes Brenz and Martin Chemnitz, do draw on Cyril, often extensively, showing a far broader and more first-hand acquaintance with the patriarch's writings.¹⁰

With these considerations in mind (first, that Luther's, or even subsequent scholarship's, identification of structural similarities between Zwingli's Christology and that of Nestorius does not yet render Luther a follower of Cyril; and, second, that Luther actually hardly knew Cyril's theology, even second-hand), it would be a considerable stretch were we to speak of Luther's indebtedness to Cyril. We can at best address ourselves to convergences in their christological proposals.

What complicates this project, however, is that the two figures find themselves on temporally opposing sides of the Council of Chalcedon and its legacy.¹¹ Cyril, who died seven years before the council convened in 451, anticipates it, though, arguably, not in a straightforward manner, while Luther consciously abides by its logic, though also, it should be argued, testing its very limits. And this is where the question of Luther's putative Cyrillianism gains some traction. Luther may actually be indebted to certain Germanic strands within mediaeval scholasticism which, without any knowledge of the Alexandrian tradition, ‘linked themselves to the Christology of Alexandria … to the point of falling into a certain amount of Monophysitism’.¹² Similarly, Richard Cross has also recently remarked that ‘Luther is the first non-miaphysite theologian expressly to adopt the view that the divine person [directly] bears his human accidents and propria.’¹³ Nevertheless, as both Marc Lienhard and Richard Cross have noted, there are also elements in Zwingli's theology that appear more faithful to the christological semantics defended by Athanasius and Cyril, such as Zwingli's understanding of the Son's divinity as infinitely surpassing the human nature, and, in this context, his insistence that it is only as nature-bearing – and so indirectly – that Christ's person should be the referent of his natures’ attributes and activities.¹⁴ This kind of logic was very much upheld by Chalcedon. We will attempt to sort this out in the following.

Divergences in convergence

The place to begin, in face of these apparently mixed interpretations, is a point of fundamental convergence between Luther and Cyril – a convergence which makes it possible to dissect their respective proposals and compare their divergences as an exercise in more than subjective association. Luther and Cyril both seem to agree on an essentially apophatic character of the incarnation; yet it is an apophaticism that calls for analysis, as long as one keeps front-and-centre the faith in what constitutes ‘the overall purpose [σκοπός] of the Incarnation’.¹⁵ That is, one must never lose sight of salvation, how this salvation is secured, and how it is now available. Cyril's words find many resonances in Luther's own call for a nova lingua, a new language unhampered by philosophical pre-understandings and logical constraints:

The way the Incarnation works is profound and cannot be expressed or even grasped by our minds, though that does not mean it is inappropriate to analyze it. Meddling in matters that do not concern us is not without its risks, and it is quite unacceptable to exceed the limits of our own intellects in our questioning and to try to think the unthinkable. Surely you appreciate that this profound mystery, which is far beyond the capabilities of the human mind, ought to be respected with an unquestioning faith.¹⁶

Or, as Luther puts it, ‘in this matter we should be wary of etymology, analogy, [logical] consequence, and examples’.¹⁷

This being recognised, there rather quickly emerges an important, contextual as well as essential, difference between Cyril's and Luther's polemical preoccupations. In his confrontation with Nestorius and the Antiochenes (Theodoret of Cyrus and Diodore of Tarsus) more broadly, Cyril devotes considerable energy to establishing and maintaining the single, unchanged identity of the divine Son – of the ‘one Lord Jesus Christ … by whom all things were made’, and who now, in these last days, ‘for us humans and for our salvation … [became] incarnate … of the Virgin Mary and was made a man’, to put this in the language of the Nicene Creed. In other words, what matters to Cyril is that the Logos of the Father be taken for the sole, unaltered referent of all his actions and titles, whether those preceding the incarnation, or those accomplished and received through his coming in the flesh and in accordance with it: ‘everything refers to him, words and deeds, both those that befit the deity, as well as those which are human’.¹⁸ In all his actions, he remains, as Cyril puts it in his signature phrase later picked up by Chalcedon's decree, ‘one and the same’, and ‘one single Son’.¹⁹

With this as Cyril's primary concern, the implications of the union remain unsystematised and even secondary. Cyril actually argues from those implications, which he simply takes for granted, to the reality of a union (ἕνωσις) – a term, as he puts it, that ‘has come down to us from the holy Fathers’²⁰ – rather than the newfangled ‘conjunction’ (συνάφεια) of the Antiochenes. That it is precisely the nature and availability of salvation that form the basis of Cyril's argument can be seen from his gloss on John 6:35, penned before the controversy with Nestorius. ‘What then is Christ promising?’, Cyril asks.

Nothing corruptible; rather, he is promising that blessing [εὐλογία, which is also a name for the Lord's Supper] in the participation of his body and blood, which raise a person completely to incorruptibility so that they need none of the provisions that drive away the death of the flesh. … The holy body of Christ then gives life to those who it enters and preserves them to incorruptibility when it is mixed with our bodies.²¹

For these kinds of benefits, as Cyril will later explicitly come to argue, nothing short of a union will do.²²

Now, what drives Luther's thinking is, likewise, the primacy of the union itself, not as a hypothetical concept, tested and clarified as one builds up to it, but as a reality that explodes all our conceptualities and is affirmed in faith on the testimony of Scripture itself.²³ Like Cyril, Luther also considers the reality of the personal union to flow directly from what he understands to be the reality of salvation, now conveyed in and through the public availability of the means of grace. But, importantly, Cyril's kind of argument will no longer suffice in Luther's context. On the one hand, in a context where the statements, ‘This is my body; this is my blood,’ together with the Lord's Supper itself, have become a site of bitter contest, they cannot but fall short of clinching the argument. On the other, Luther also fears that the Christology he has been taught, broadly founded upon Cyril's primary concern, remains crucially underdeveloped and so actually offers little help.

We must emphasise here what we have already alluded to above, namely, that the anti-Nestorian bluster of Luther's polemic may easily obscure the fact that Luther considers Nestorianism to be not some arch-heresy beyond the pale, but a lingering problem of orthodoxy. Luther's focus in all his writings oriented to the metaphysics of the incarnation is on the ambiguity of the communicatio idomatum in the orthodox tradition. For on closer scrutiny this tradition is not immune to the reduction of christological realities to a matter of verbal predication, to rules of identification and proper speech; at its best, it attends to the identity of the subject but fails to draw more far-reaching implications.

And so, while for Cyril pointing to Christ's life-giving flesh simply necessitated the single referent of all Christ's actions – the eucharistic body and blood could not but be the very flesh of the Logos – the reverse, as Luther is all too aware, offers no similar guarantee. Naming the divine Son as the single referent of all his actions does not secure the objective presence and subjective reception of his body and blood in the Lord's Supper. Luther is thus far more – and more consciously – than Cyril, interested in spelling out the nature of the union, in the hope that correct salvific implications will then follow and the lingering Nestorianism will at long last be put to rest.

Beyond verbal predication

On many occasions and in a variety of contexts, Luther appeals simply to the communicatio idiomatum, the communication of properties. Conventional as this language sounds, Luther's interest, as we have noted, is hardly in the grammar of Christology. What somewhat clouds Luther's own underlying concern is his lack of precision when it comes to distinguishing between statements such as, on the one hand, ‘This Israelite, Jesus, created the universe,’ and, on the other, ‘The eternal Son of God suffered.’ The former is largely a matter of doing justice to the oneness of Christ's person by emphasising a single referent: the Son, who ‘when the fullness of time had come [was] born of a woman’ (Gal 4:4), is none other than ‘one and the same’ (in Cyril's and Chalcedon's language) divine Son who is ‘the firstborn of all creation’ (Col 1:15). This kind of statement could be likened to asserting that the first U.S. President was born in the British colony of Virginia.

It is the latter statement, however, that is the crux of the issue. Much as he speaks to what must and must not be said about Christ and under what conditions, Luther wants more than correct predication that infallibly picks out the Logos. For Luther, to quote his polemical ‘confession’ against the Swiss, it is a matter of life and death that Christ not be turned into a Messiah ‘who is and does no more in his passion and his life than any other ordinary saint … a poor Savior for me’, himself in need of a Saviour.²⁴ What matters to Luther, I believe, is Christ's agency – a concern lying beyond the question of mere identity, though it presupposes it. What occupies Luther is doing justice to Christ as a unitary agent, an agent whose actions, or rather whose very life itself in its divine and human dimensions, are all characterised by an essential unity and congruence. As Luther famously put it, ‘if it cannot be said that God died for us, but only a man, we are lost; but if God's death and a dead God lie in the balance, his side goes down and ours goes up like a light and empty scale’.²⁵

With Christ's unitary agency being the pressing issue, what first comes under Luther's scrutiny is the meaning of divinity and humanity. To begin with, in his Disputation on the Divinity and Humanity of Christ (1540), even as Luther insists that ‘the unity is what is fundamental’,²⁶ the reformer is quick to clarify that Christ's divine and human natures are ‘joined together like no other thing’, with their distinction actually confirming the union.²⁷ Then, proceeding from this crucial assumption, namely, that God and humanity are united in Christ, Luther goes on to make a significant conceptual shift in how he thinks of the divine. For example, in another disputation from the same period, on the Johannine ‘The Word was made flesh’ (1539), Luther does not juxtapose God's infinity with human finitude. That, he says, is a philosophical approach. It is the same kind of approach that ultimately proved to be the undoing of Nestorius’ teaching on Christ, despite his best intentions: ‘[t]o be God is an immeasurably different thing than to be man; that is why the idiomata of the two natures cannot coincide. That is the opinion of Nestorius.’²⁸ Whether Luther is right about philosophy here is beside the point. One could certainly appeal to Nicholas of Cusa's notion of God as not-other; or, if we were to put it with more precision, God's infinity must be viewed along the lines of what Hegel will later call the true infinite. In short, God's infinity is none other than an aptitude for finitude.²⁹ In the same manner, Creator and creature, God and the human, need not be opposed to each other.³⁰ Luther likewise argues that the incarnation, theologically speaking, in no way entails the curtailment of the infinite by the finite, a rather traditional point on the face of it; but what Luther insists on is that the incarnation is the very manifestation of divine omnipotence.³¹ And he goes on to argue, in the 1540 disputation but much in the same vein, that it is only ‘in philosophy’ that immortality and mortality are antithetical.³²

In this context, it is especially interesting to observe that Luther changes his mind in his later trinitarian disputations (1544–45) about the capacity of the divine essence to generate.³³ He parts ways with Peter Lombard's philosophical position that the divine essence does not generate. It certainly does, for the divine essence is none other than the persons of God's triune life, who stand in generative relations to one another. The upshot is a less speculative and more actualist approach to divinity. But Luther gets there from a more philosophical standpoint, too. In the Disputation on the Divinity and Humanity of Christ, he notes that the concrete noun, ‘God’, and ‘divinity’ are synonyms. ‘In the divine predicates or attributes there is not a difference … between the concrete and the abstract’;³⁴ and so, ‘the divine nature[, when it is taken for a person, was born of Mary] in the person of Christ’.³⁵ It is as if Luther were saying, God is God, emphasising the subject rather than the predicate: God determines divinity, or rather divinity is God's own; God does not enact or live up to some independently derived idea of divinity!

Luther's insistence on the primacy of the divine persons, who in their actuality posit the significance of divinity, offers an insight into how the reformer ultimately construes the divine and human in Christ. We must also add here that Christ not only determines the significance and actuality of the divine, but the meaning of the human, as well. Christ does not simply instantiate humanity; he redefines it – ‘for here is one man to whom no one is similar’.³⁶ We, too, find our humanity not in ourselves but in being justified by God.³⁷ Thus divinity and humanity need not be seen as fundamentally at odds. In the Disputation on the Divinity and Humanity of Christ, Luther insists: ‘here in Christ: God and man are joined together in one person and must not [sic] be distinguished’.³⁸

Cyril on the signification of divinity

When we compare all this to Cyril, two options present themselves. First of all, Cyril certainly lacks the equivalent of Luther's actualism. But there is another strand of the tradition that may be operative in his work, with much the same result of not being compelled merely to fit together divinity and humanity as fundamentally irreconcilable qualities. When Cyril asserts that the Logos, ‘[i]mmutable [and unalterable] by nature … remains that which he was and is forever … without confusion or change’,³⁹ this may be taken as an assertion of the continuing identity of the Logos, rather than a statement of what his divinity, as such, positively entails in distinction from humanity.⁴⁰ On this reading, immutability and unalterability would thus amount to merely negative assertions that God is not mutable or alterable in the way God's creation happens to be. And so, when such statements are made, what matters is not how God might be mutable or immutable, but that in all God does, God is consistent with God's own self in a way beyond the grasp of worldly experience. God is God. This venerable, even if inconsistent tradition, goes back at least to Gregory of Nazianzus in his polemic against the Eunomians, especially their insistence on the self-evident character of theological language and their consequent elevation of dialectic.⁴¹

Some of Cyril's statements, especially in his earlier On Orthodoxy, seem to corroborate this reading. He observes: ‘It is not a case of the single Christ, Lord, and Son merely being a juxtaposition of divinity and some flesh, but rather he is paradoxically bound together out of two complete elements, namely, humanity and divinity, into a single individual.’⁴² Cyril seems to see the value of distinguishing the two natures as largely noetic and identity oriented: ‘It is appropriate for one's mind to sense a distinction between the natures (after all, human and divine natures are not identical), but at the same time as this acknowledgement, the mind must also accept the concurrence of the two into a unity.’⁴³ He then adds that ‘we must neither completely disentangle the Word of God from the humanity after his convergence with the flesh, nor deprive the humanity of the glory that belongs properly to divinity, so long as we think and speak of this as being in Christ’.⁴⁴ While Cyril never comes close to Luther's ‘God's death and a dead God’, these statements do imply that divinity need not simply be antithetical to humanity, but supremely itself in its openness to humanity. ‘Just as the condition of being the Only-Begotten, which belongs especially to Christ, became a property of his humanity when the latter was united to the Word …, so also in turn did the conditions of being “one among many brothers” and of being the firstborn become properties of the Word after being united to the flesh.’⁴⁵

This said, there is much in Cyril to suggest that this is only a secondary and muffled aspect of his Christology. To be sure, in his later On the Unity of Christ, he defines the union as ‘the concurrence in one reality of those things which are understood to be united’.⁴⁶ More often than not, however, one gets the impression that Christ's divinity, precisely as transcendent, stands not in openness but at a remove from his humanity, and so does the Son himself when considered apart from the economy: ‘economically submitting himself to the limitations of the manhood … while at the same time he authentically enjoyed transcendent divine status within his own essential being’.⁴⁷

This is, arguably, reinforced further by Cyril's notion of ‘economic appropriation’, which conveys the Son's relationship to his humanity: ‘Just as we say that the flesh became his very own, in the same way the weakness of that flesh became his very own in an economic appropriation according to the terms of the unification.’⁴⁸ To be sure, appropriation does entail that none other than the Logos is himself the subject of his human actions, as John McGuckin has tirelessly emphasised⁴⁹ – but what is also conveyed is an ever-renewed decision to re-engage, to appropriate, to make one's own. Here Cyril's notion of the flesh as a type of instrument (ὄργανον) becomes particularly relevant;⁵⁰ and so does his observation that the flesh serves as a veil for the Logos. ‘The Word is made one with [his flesh], and in turn it masks the transcendent excellence of the eminence and glory of the Word form being gazed at as if laid bare to the inspection of all.’⁵¹ It is as if the divinity of the Son does not so much facilitate as distance the Logos from the actions exercised in his assumed nature, so much so that those actions ever require intentional appropriation. This kind of language is altogether absent from Luther.

The effects can be seen in how Cyril speaks of the suffering of the Logos. He writes that the Word ‘wished to suffer, even though he was beyond the power of suffering in his nature as God, then he wrapped himself in flesh that was capable of suffering, and revealed it as his very own, so that even the suffering might be said to be his because it was his own body which suffered and no one else's’.⁵² What is interesting in this passage is that, while the intention to suffer, belongs to the Logos, suffering itself is a passion of the humanity, which is then ascribed (‘the suffering might be said to be his’) to the Logos as his own. But Cyril leaves no doubt that, ‘The Word was alive even when his holy flesh was tasting death, so that when death was beaten and corruption trodden underfoot the power of the resurrection might come upon the whole human race.’⁵³

If what we have just outlined is indeed the dominant strand in Cyril's Christology, then the fundamental difference between Cyril and Luther boils down to an excess of divine agency and, indirectly, perhaps even identity on the Logos’ part. The Word's agency remains in crucial aspects parallel, indifferent, non-overlapping, and essentially unreceptive to the Word's economic activity.⁵⁴ The referent of all the actions, whether divine or human, is, to be sure, the same: the Son, who remains none other than the divine Son, even when veiled in the flesh. But if Cyril's emphasis on the Son's divinity is taken for more than a statement of continuing identity, if it is seen as positively and of itself substantive – then what we find in Cyril are only partially overlapping agencies whose convergence always borders on accidental. Consider Cyril's take on the resurrection: ‘There is nothing shocking about the Word from God not remaining in Hades since he fills all things and lives among all by the energy and nature of his divinity in a manner that can hardly be described. Divinity cannot be located or enclosed or in any way measured, nor contained in any way at all.’⁵⁵ In other words, Christ must rise in his humanity for no other reason than that it converges with his divinity, which simply does what it does.

Luther's human God

In Luther's context, this will no longer suffice. It will not suffice to undergird a realistic view of the Lord's Supper, where the body and blood of Christ are received by all to eat and to drink; and it will not suffice, more broadly, where salvation is understood as a matter of trust. In response, Luther offers an account of Christ's united agency by attending to the reality of the hypostatic union and privileging Christology and the doctrine of the Trinity in spelling out the nature of divinity. Luther's account is, to be sure, apophatic, in that it comes complete with a plea for simplicity of speech, a recognition of the inadequacy of language and grammar, and a certain despair of arguments over words.⁵⁶ But this does not imply a lack of clarity. Luther's is, in the end, a coherent view of the co-extensiveness of agencies.

The reformer's operative principle is ‘wherever you place God for me, you must also place the humanity for me [wo du mir Gott hinsetzest, da mustu mir die menschheit mit hin setzen]’.⁵⁷ Or, to quote a longer and clearer elaboration of this thought,

if you could show me one place where God is and not the man, then the person is already divided and I could at once say truthfully, ‘Here is God who is not man and has never become man.’ But no God like that for me! For it would follow from this that space and place had separated the two natures from one another and thus had divided the person, even though death and all the devils had been unable to separate and tear them apart.⁵⁸

As Luther sees it, even though we certainly cannot grasp all that God is doing, his divine hiddenness will in the light of glory be revealed as also coordinated by God's human face eternally luminous at the Father's right hand.⁵⁹ Divine and human activities are not at cross-purposes; they are not even, and not in the least, mutually indifferent. They are, rather, co-extensive and so truly united.

Where the integrity of the Lord's Supper as the Lord's own meal is at stake and where faith has the character of receiving oneself from God in trust, nothing but a congruent conception of Christ's divine–human agency will do. To this end Luther insists: ‘what is done by the human nature is said also to be done by the divine nature, and vice versa’.⁶⁰ And just to make sure that this statement is not merely a matter of a single referent, as in the statement, ‘This man created, the universe,’ Luther goes on to explain:

From eternity [the Son] did not suffer; but when He was made man, He was passible. From eternity He was not man; but now being conceived by the Holy Spirit, that is, born of the Virgin, God and man are made one person, and the same things are truly predicated of God and man. Here the personal union is accomplished. Here the humanity and divinity are intertwined.⁶¹

To recall Luther's confrontation with the Nestorians of his own day – ‘Nestorians who’, as he puts it, ‘fought me very stubbornly, saying that the divinity of Christ could not suffer’ – Luther asserts there is no divinity apart from the life of the Father, Son and Spirit, and apart from the now and forever incarnate person of the Son. Divinity is always and only concrete. God is God.

There yet remains the most important implication to be drawn from Luther's perspective – one that, I believe, forms its decisive dimension. Luther's christological thought certainly lacks the impressive structural architectonic of his followers’, and it is less than theirs beholden to Cyril's Christology in terms of the need to find a precedent and verify one's guiding commitments. Yet precisely due to all of this, Luther sees that what is necessary is not merely securing the unchangeable identity of the divine–human subject. The debate with the Swiss, as we have repeatedly noted, has little to do with simply securing a single referent. Neither, however, is it concerned with the capacity of humanity to convey the divine. It is not quite Luther's concern that the flesh of Christ be life-giving, as it is for Cyril. This, from Luther's perspective, is too limiting a view of the matter. For it does not put to rest the threat of incongruous agencies. And because it fails to diffuse this possibility, as Luther seems to be very much aware, it runs the risk of undermining precisely what it seeks to secure: the life-giving character of Christ's flesh. From Luther's perspective, when such a denial does appear in the course of Christianity's doctrinal development, it is not a heretical imposition but an outworking of a possibility that was long conveniently regarded to be impossible but not, as such, disarmed through the Christian tradition's theological self-critique.

In order to grasp Luther's conscious unwillingness simply to fall back on the received patterns of thought and argument, let us consider the following. On the face of it, it may sound desirable simply to assert that the Lord's Supper is essentially about ‘preserv[ing us] to incorruptibility when it is mixed with our bodies’, as Cyril saw it⁶²; or about the communication to the recipient of qualities that are above and even contrary to human nature, as the later Lutherans would argue. Nevertheless, if receiving the body and blood of Christ under the visible elements of bread and wine has as its focal point the infusion of divine energies, so that they might come to inhere in the recipient ‘formally, habitually, and subjectively’,⁶³ then any suggestion of the Logos carrying out some of his divine activities outside of the assumed humanity will eventually call into doubt the integrity of the Supper. For after all, is it not in the Logos’ own proper nature, and certainly within his power, to remain untethered from his humanity, and even more so its sacramental vehicles?

And so, by going beyond a merely Cyrillian view of the Supper, Luther is not only rejecting Zwingli's position, but also anticipating and already setting aside, what will emerge as John Calvin's view of the Sacrament. Crucially, Calvin sees no problem in arguing away as impossible a union of the bread and Christ's body, or what this really amounts to: the presence of the body and blood of Christ in the sacramental elements. The ascension, as Calvin understands it, has effected a spatial removal of Jesus's body from earth, though, of course, the Logos in his divinity is in no way affected by this.⁶⁴ At the same time, however, Calvin remains adamant, contra Zwingli, in stressing ‘the true and substantial partaking of the body of the Lord, which is shown to believers under the sacred symbols of the Supper’, a partaking ‘not … solely by imagination or understanding of mind, but [so as] to enjoy the thing itself as nourishment of eternal life’.⁶⁵ The only way Calvin is able to reconcile these two commitments is by subordinating the validity, that is, reality and integrity, of the Lord's Supper to its efficacy. Faith is what renders the sacrament efficacious, or salutary, for the recipient. That very faith is now said to elevate the individual believer to heaven, there to partake of Christ's body.⁶⁶ With the reality of the sacrament dependent on one's personal faith, the believer emerges as the sacrament's centre and somewhat unintended focal point.

Notably, in proposing this very solution, Calvin stands in serious danger of losing the sacrament altogether, as its efficacy must itself become uncertain, as well. For, when all is said and done, Calvin ends up burdening the believer with a debilitating task of soul-searching. The believer must now assure not merely worthy reception of what is antecedently established and already provided by God – where worthiness lies simply in faithful recognition of God at work in supplying, in a divine–human way, the gifts of the new creation, as is the case for Luther and the broader catholic tradition. The believer must, rather, personally establish and discern access to God's divine–human gifts, for only as elevated to heaven by faith can one partake of Christ's body and blood. Only there can the sacramental eating prove to be life-giving.

In all this, Calvin ends up postulating more than he might have wished. The Lord's Supper in its mundane dimension conveys no indication at all that God is for me, and thus, that it might prove at all efficacious for me. What emerges as the object of trust is, above all, one's own faith, or some subjective surrogate for it. Efficacy migrates ever so subtly from faith grasping the sacrament for what it is to a faith grasping itself, as a precondition of grasping the ways of God towards me in the Lord's Supper. But what gets reinforced in the process is simply the inscrutability of God's ways over and above the Son's humanity and the sacramental means of conveying it to us. And so, the sacrament cannot but become an unnecessary and always potentially vacuous detour for a faith that really is on the lookout for itself. This, we should add, is only exacerbated further by Calvin's insistence on God's double decree of predestination.

What, then, is Luther's alternative to Cyril's sacramental emphasis that avoids the inherent danger of a self-referential faith? Before we address ourselves to this question, we should note that Luther spells out his eucharistic commitments long before the rift with the Swiss, and, of course, any long-standing Lutheran-Reformed polemics. Hence, importantly, Luther's sacramental theology shows itself to be an intrinsic product of his christological reflection, even as this reflection is sustained by the eucharistic commitment that undergirds it. Thus, as early as his On the Babylonian Captivity of the Church (1520), Luther insists that it is not the eucharistic bread and wine that, in some realistic sense, symbolise or convey the body and blood of Christ for our salvation. It is rather the body and blood of Christ that symbolise and convey God's ongoing favour.⁶⁷ More specifically, they are vehicles of God's promise to be pro me. As such, they necessarily point to the inalienable presence of the divine Promisor. Though Luther does not quite develop an ontology of the promise, it is clear that for the promise to be believable and to be believed, the Promisor must stand by it (and thus by the gifts which indicate it) with his whole being. He himself must ultimately be, and truly is, the gift. What this amounts to is that the promise can be believed because the body and blood are not accidental to the divine promisor; his humanity is not accidental to him, but intimately his own in the depth of his divine being. The sacraments – not just the Lord's Supper, but also baptism and the word of absolution – are nothing but a self-demonstration of the Promisor in his inmost being.

How important this dimension is to Luther can be seen also in his account of baptism:

it is not man's baptism, but Christ's and God's baptism. … Ascribe both [the outward and inward part] to God alone, and look upon the person administering it as simply the vicarious instrument of God, by which the Lord sitting in heaven thrusts you under the water with his own hands, and promises you forgiveness of your sins, speaking to you upon earth with a human voice by the mouth of his minister.⁶⁸

In all this, God's capacity to convey his grace through material means does not lie in those gifts serving as a ladder to an inner, spiritual reality or truth. They themselves are the truth, bringing one face-to-face with a God who not only does not shy from our condition but has made this condition his own, meeting us in it with his very own human face and action.

Luther's concern is thus that Christ himself be able to offer his body and blood in the Supper as a token of the triune God's favour.⁶⁹ Whereas Cyril, just like Luther's heirs later, is interested in affirming the fullness of divinity manifesting itself in and through the assumed human nature, what seems to matter to Luther is, rather, that the fullness of humanity should be displayed by the divine Son as his very own, that is, as a manifestation of his divinity. Thus, on Luther's account, in the end the Son's divine agency simply is human agency. And this human agency is none other than the concreteness of the Son's divine action. There is no transcendent beyond, or hidden excess – the beyond is only the Father and the Spirit in their positing of the Son.

As we approach the conclusion of this article, we should finally note what has long been gestured at. Luther's realistic position goes beyond Cyril's own realism in regard to the union. For Luther, God is for me, abidingly for me, because in his divinity God bears my very nature – in the depth of his divinity God himself is human. Humanity is with God, and before God as his divine self-determination. In this way, that is, by thinking from the union out as the precondition of salvation, Luther offers a view of christological agency that secures not only this salvation but also its continuing availability through God's ongoing action in correspondence with his gifts. God himself remains the Giver – the Speaker, the Baptiser and the Nourisher in relation to his people for the sake of life everlasting. Because God's agency always has, as it were, a human face, those gifts do not merely convey, by infusion or otherwise, life or grace. Much more specifically, applied by God himself, they invite one into a personal relationship. The gifts are pledges of the presence and, even more so, of the character of the divine Promisor, who in the incarnation has declared himself to be inalienably for me. God's own divine–human action in his gifts summons me into a relationship of trust, into faith.

Conclusion

When we put Cyril and Luther side by side, we certainly recognise the convergence of their fundamental commitments, which they both, in their own way, take for granted. Yet, the arguments they pursue to honour those commitments differ quite significantly. What Cyril wishes to secure, namely, the unchanging identity of the referent of all of Christ's actions, much as it is a fundamental step, is no longer sufficient in Luther's day. Cyril can afford to leave certain aspects of the union ambiguous, or even suggest a certain divergence of divine and human agencies. What matters to him is that the humanity, as such, convey the fullness of divinity. This desideratum can be met without the need for divinity to be coextensive with the latter. By contrast, where the Lord's Supper is hotly contested, Luther must begin from that which Cyril defended, the unchanged, single identity of the divine Son. But to stop here, as Luther sees it, is to keep the door wide open for a renewed Nestorianism to creep back in. Luther, therefore, feels compelled to go beyond Cyril's position. Rather than rely on Christ's humanity conveying the divine, Luther believes that only when divinity can bear humanity as its own can God's sacramental presence in his body and blood be assured and God himself be trusted for salvation, since he himself unambiguously offers it in his ongoing divine–human action.

In the end, we should doubt that Luther's declared opposition to Nestorianism makes him recognisably Cyrillian. This is, in part, due to the theological circumstances that shape Cyril's and Luther's respective defenses of the Christian faith, as well as, more importantly, due to the internal logic of their approaches. Luther, to be sure, builds off Cyril's defense of the Son's single identity. But this is, for Luther, simply a given of the catholic tradition – a given that on its own can no longer secure some long-standing commitments. Luther's Cyrillianism is thus simply Luther's faith-mindedness. This said, what the two towering theologians do share in common is a commitment to the kind of theological imagination in defense of the faith that resists the compellingly systematisable. In this, they both push against Chalcedon: Cyril from the position of a certain apophatic excess, and Luther from a standpoint sceptical of the narrowness and proneness to mislead on the part of received formulas.