In his theology of the Eucharist, Zubiri brings together his entire theological outlook in a single unity, and thus, it is aptly described as the "fullness of Christian life." His concept of the glorified body is used within his overall metaphysical system to frame the Real Presence as the way in which the Christian is molded (deiformed) into the life of Christ. I commend the entire discussion as it is probably the best tool for understanding the overall picture of Zubiri's theology, and the six parts of can be found in order here, here, here, here, here, and here (all parts and cited materials therefrom © 2001-2005 by Joaquín Redondo. Permission to republish in any form is hereby granted, provided that source is acknowledged). There is some redundancy between the sections (the Appendix reproduces some material from the preceding chapter), but I think that it is probably a useful sort of redundancy given that the slightly different explanations may serve to highlight different features of Zubiri's metaphysics. What I would like to do is to briefly introduce from the Appendix some particular concepts that may not be apparent at first glance in order to provide something of an introduction to Zubiri's doctrine of the Eucharist.
After affirming that both faith and the language of Scripture itself demands that we think of the presence of Christ as being real, Zubiri begins his conceptive description of the Eucharist by defining the reality of the bread itself.
What is this bread in which Christ is present? The very fact that Christ should invite one to eat the bread, already tells us that here “bread” does not signify a physiochemical reality. It is not a matter of the reality of the bread in and of itself, but of the bread insofar as food, i.e., bread sub ratione alimenti. The ratio of food and the ratio of physiochemical reality are not the same. As early as the thirteenth century, St. Thomas and St. Bonaventure discussed this problem without reaching agreement. For St. Bonaventure, there is no presence of Christ except when the bread is food. He believed that mice are not nourished by bread, and affirmed in consequence that Christ is not present in consecrated bread if the rodent eats it; such bread does not have ratio alimenti for the mouse. St. Thomas, on the other hand, thought that the presence of Christ is a presence in the bread qua reality, in and of itself. In all modesty, I think that St. Bonaventure {400} was right. In the Eucharist, bread is bread as food, and not as the physiochemical reality of bread. Food is principle of life; to be food is to be principle of life. Because of this, Christ is present in the bread as food, as principle of life. The presence of Christ in the food signifies that Christ is principle of life.
Zubiri can then explain the difference between the reality of the bread in terms of physical properties ("notes") and the substantivity of the bread, the greater unity to which these properties belong and in which the true reality of the thing subsists, the way in which the bread is de suyo (in its own right) with respect to other things. Zubiri reminds us:
Substantiality and substantivity are very different things. As I see it, things are formally constituted by properties, signs, qualities (the terminology is unimportant now) which cohere with each other; each one, as a property, is a property of all the rest, is a “property-of”. This is what I call the “constructed state”, taking the term from the grammar of Semitic languages. In the constructed state, the terms among themselves, and therefore that which they designate, formally constitute a proper intrinsic unity. And this unity of the constructed state is what I call “system”. The constructed state is the intrinsic and formal unity of two nouns, and therefore of two things. If I say, in any Indo-European language, “son of Peter”, I have two nouns and two realities, son and Peter, the one dependent on the other. But in the constructed state I have, {402} as it were, but one noun and one thing, constructed in two of its moments, as if I were to say “son-of-Peter”. I fully realize that one of these moments is called the “absolute state”, but this term is absolute because it is the base on which the whole thing is constructed. Applied to our problem, the idea of the constructed state is what I have called “system”. Each of the moments of a system is built upon the system’s own unity. Radically and primarily, then, things are systems of properties; each property is a “property-of” the system. This system has two moments. One is that by which the properties in themselves are something “complete” in the order of properties; each property is a property of the others, in a sense, cyclically. But there is another moment. Taking the thing by itself, this complete characteristic of the system is a closed and total unity. It is not a unity by reason of the properties, but a unity with its own characteristic, a characteristic by which the already complete has the sufficiency to be a closed and total unity. By virtue of this second moment, the properties of the thing are not only complete, but they also have the sufficiency to determine the thing as “one” thing. This sufficiency is what I call substantivity. Substantivity is the sufficiency to be a closed, total unity. Both moments, that of being complete and that of being a closed and total unity, are not independent. Complete properties modalize the systematic unity of the substantivity. And this modalization is what I call “constitution”; it is the manner of being “one” by virtue of the complete properties. It is the manner by which “one” thing is “this” thing.
Thus, it can be true that there is a real change in substantivity, as something becomes part of a greater unity, without necessarily having a change in physical properties. This is what Zubiri calls transubstantivation:
The two moments to which I refer (I repeat, being complete in its properties and being a substantivity) are not identical. The unity of substantivity can be opened without destroying the complete character of the properties. This opening is what allows substantivity to change without changing the properties. Substantivity can be acquired and lost in many ways, and always formally without changing properties. Thus, glucose in a jar is something, which classical metaphysics called “substantial”, but at the same time it is something substantive. On the other land, when it is ingested by an organism (apart from the metabolic alterations), despite preserving whole its presumed substance and its properties, it has nevertheless lost its substantivity. Substantivity is had only by the whole organism; only the organism is the closed and total system. For this reason, the substance itself of the glucose is, in the organism, perfectly unsubstantive. The radicality and primariness of things is not, then, substantiality, but substantivity. And the transformation of substantivity is not even remotely a transformation in substantiality; it is not a transmutation of realities. The transformation of substantivity consists in that the system of properties loses its constitutional unity. It is an opening of the unity of substantivity in favor of a unity of a superior order. Then the properties no longer totally modalize the substantive unity. This substantive unity then has a different mode, a different constitutive unity. In the case of the organism, this is a substantive unity, which is not constitutionally modalized only by the properties of the glucose. In turn, the new unity does not necessarily constitute a new property of the glucose. Thus, the unity of the organism is not a new property, but only a different unity, which is merely {404} functional, etc. The opening of the unity of substantivity can take place, then, in many different ways. Ingestion is no more than one of them, there are others.
In like manner, the incorporation of the consecrated Host into the substantive reality of Christ changes the real state of bread as "meaning-thing" (reality in respectivity to others, i.e., substantivity) into that of spiritual food: the Bread of Life. Conceptively, it is not a question of transubstantiation, but transubstantivation:
Thus, we must ask ourselves what relation there is, so to speak, between this conversion of substantivity, and the real presence. Classical metaphysics has thought that the real presence is a consequence of the conversion. Since there can be no accident without substance, the substantial conversion determines the presence of the substance of Christ in the bread. Whether this conversion is understood as a formal conversion (according to St. Thomas) or as an equivalent conversion (according to Suárez), the basis of the real presence is always seen as the conversion. With all due respect, I propose a different view. I believe that the conversion is the consequence of the real presence of Christ in the bread-food. The real presence is the basis of the conversion. Only because Christ is present in the bread, this bread, as food substantivity, has lost its material substantivity, and acquired a substantivity {407} of spiritual food. By the real presence of Christ the bread is converted ratione alimenti. The conversion formally affects the condition of the bread.
Of course, this conversion of substantivity is with respect to a particular kind of respectivity; specifically, bread as physical nourishment and Christ as spiritual nourishment. It can be contrasted with the Incarnation particularly in that, as a closed essence, the bread has limited significance (capacity as "meaning-thing"). Its significance in that respect is entirely subverted to the conveyance of the the superior meaning of Christ as spiritual food; its substantivity is entirely replaced. In the contrasting case of Christ's humanity, Christ's human substantivity is still fully present, but the his-ownness, the reality-making property of the open essence, the I, is the divine Word of God. Thus, as Zubiri puts it, the Real Presence is not a case of "in-breadification" analogous to the Incarnation.
At the same time, the Real Presence is an actual bodily presence, and Zubiri must also account for this as well. To do so, Zubiri first recalls his idea of the glorified body [NOTE: One might draw a parallel between Zubiri's treatment of the glorified Body here and St. Cyril's argument in reverse from the life-giving qualities of the Eucharist to the divinized flesh of Christ, contra Nestorius.]:
In its organization and in its proper configuration the body determines the real and physical presence of man in reality. According to this moment, then, the body is a corporeity. That man is corporeal means that corporeity is the very radical principle of being here-and-now present in reality: the body is sôma. This is, as I see it, how “body” has been able to signify “I, myself”, it is I myself who is present “here”. Let us not, then, confuse body and organism [structural organization]. Body is corporeity, and as such, is the intrinsic and formal principle of actuality.
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In fact, these three moments or functions [organization, configuration, and corporeity] are not separable. {413} But this is so only in fact. To be a principle of actuality does not imply its being so “of its own” (Sp. de suyo) nor having configuration or organization. Let us say in passing that this moment of principle of actuality, with neither configuration nor organization, is what constitutes, from my perspective, the “glorified body”. The glorified body will be neither an organism nor a configuration; rather it will be, from my point of view, purely and simply a principle of actuality in God, and in the rest of those glorified. How? We do not know. Let us not lose ourselves in fantasies and imaginings. It is enough to have conceptualized it.
In the glorified body, only the essential moment of the body (i.e., corporeity, presence) is included. Thus, in making His presence actual in the Eucharist (transactualization), it is a bodily presence of His glorified flesh, and it is by virtue of this bodily presence that the Bread is transubstantivated. The Real Presence of the Body is what makes the bread spiritual food, rather than vice versa. All that remains for Zubiri is to explain the effect of the Eucharist, the formal reason for its being, and this comes exactly from the idea of Eucharist as Sacrament of communal eating:
But communion is only one moment of the formal reason for the Eucharist; we need to ask ourselves, in what does the unity of this personal communion consist? This unity is in man a unity of actuality. And the principle of human actuality is what constitutes corporeity. The body is formally a principle of actuality. Hence, it follows that in the personal communion of the participants in the agape with Christ, Christ is actual in each one of them through His principle of formal actuality, i.e., through His body. The participants in the agape, upon acquiring an actuality in Christ, thereby form a body with him, and by its virtue their personal communion with Christ is precisely, and formally an incorporation into the body of Christ. And since all form a single body with Christ, it follows that, as St. Paul tells us, we are all co-corporeal in Christ. The idea of the body of Christ, of incorporation to Christ, and of co-corporeity is expressed in St. Paul. The formal essence of the Eucharist is personal communion, and the essence of personal communion is incorporation to the body of Christ. And since body is the actuality of the “I, myself” in reality, it follows that this incorporation consists in the fact that each participant in the agape is “I, myself”, being I in, and by the I of Christ. Every Christian is another Christ.
With that introduction, I highly recommend that you review Zubiri's entire discussion of the subject, as it is an excellent "test case" to see how Zubiri integrates metaphysics with theology.
