By David Farina Turnbloom
When I teach Eucharistic theology to undergraduate students, the Roman Catholics among them are usually eager to discuss the issue of Eucharistic change: How do the bread and wine become the body and blood of Jesus?
I do not think these students are unique in harboring this preoccupation. As a child and as a young adult, my catechesis regarding the celebration of the Eucharist perpetually emphasized the ‘real presence’ of Jesus in the Eucharist. Emphasis on this ‘real presence’ is certainly still at work in our catechesis not least of all because it is clearly emphasized in the Mass itself. We kneel, bells ring, the presider elevates the host, etc. In Roman Catholic theology, the miraculous part of Mass is the moment of consecration. It is understandable that miracles draw our attention. The very concept of miracles seems to imply a level of importance that outshines the non-miraculous. The result, however, is that the rest of the Mass often appears mundane in comparison. Even receiving the Eucharist during the Communion rite often becomes (to use a metaphor from theater) the falling action after the theatrical climax.
So, my students have learned to think of Eucharistic theology as explanations of ‘real presence,’ and chief among the traditional examples of this narrow form of Eucharistic theology is the metaphysical theory of transubstantiation constructed by St. Thomas Aquinas in his great work, the Summa Theologiae. It is common for Roman Catholics (and other Christians) to immediately think of transubstantiation when they think of Aquinas. Indeed, as I will point out below, Aquinas went to great lengths to offer a description of how Jesus becomes substantially present in the Eucharist. However, based on my reading of The Summa Theologiae, I argue that Aquinas’s highly technical theory of transubstantiation more often than not proves to be a distraction from his true vision of the Eucharist.
If I were asked to summarize the Eucharistic theology of St. Thomas Aquinas I would repeat the following passage from the Summa Theologiae: “Spiritual food changes man [sic] into itself.” In this succinct passage, Aquinas chooses to describe the Eucharist as food with a purpose. As I will now argue, this short description is an apt summary of his entire Eucharistic theology. The Eucharist finds its true purpose, not in the presence of Jesus’s substance, but in the living friendship of the Church, the true and living Body of Christ on earth. In order to understand what Aquinas means by ‘spiritual food’ I will begin with a brief examination of some modern criticisms of his Eucharistic theology.
I. Criticizing Aquinas: Substantial Existence is not Real Presence
In 1944 the French Jesuit and Catholic cardinal Henri de Lubac published a book titled, Corpus Mysitcum: Essai sur L’Eucharistie et l’Église au moyen âge. In this text, de Lubac traces the history of what he calls the “threefold Body of Christ:” the historical body (Jesus of Nazareth’s arms, legs, torso, etc.), the ecclesial body (the Christian community as the Church), and the eucharistic body (the consecrated bread and wine of the Eucharist). Throughout Christian tradition, each of these bodies has been understood as a real presence of Jesus Christ. He begins his text by saying that, “In the thinking of the whole of Christian antiquity, the Eucharist and the Church are linked. . . . The Eucharist corresponds to the Church as cause to effect, as means to end, as sign to reality.” In other words, for the entirety of Christian tradition, the ecclesial body of Christ was an intrinsic aspect of the Eucharist. Thinking about the Eucharist without thinking about the life of the Church would have made little sense. The eucharistic body of Christ existed to serve the ecclesial body of Christ.
However, according to de Lubac, over the course of many centuries there arose a “deadly dichotomy” that separated the ecclesial body of Christ from the eucharistic body of Christ. For de Lubac, this “deadly dichotomy” is our tendency to focus so intensely on the relationship between the historical body of Christ and the eucharistic body of Christ that we forget about the relationship between the Church and the Eucharist. Put differently, we so frequently ask how Christ is present in the Eucharist that we stop asking why Christ is present.
To reiterate de Lubac’s concerns, the French sacramental theologian Louis-Marie Chauvet has invoked the difference between esse (a Latin word for ‘being’) and adesse (a Latin word for ‘being for’). When we focus intently on the relationship between the historical body of Christ and the Eucharistic body of Christ, we end up focusing on how Christ exists in the Eucharist. In other words, we look at the Eucharistic body of Christ and see an esse: a being that exists due to the miracle of transubstantiation. This Eucharistic body of Christ can be isolated (e.g. in a tabernacle, in a monstrance, on the altar, etc.) and it will exist regardless of who knows about it or where it is located. If, however, we can avoid the deadly dichotomy and prioritize the relationship between the Eucharistic body and the ecclesial body, then (instead of seeing an esse) we tend to see the Eucharistic body of Christ as an adesse: a being that is present for the Church. The difference between esse and adesse is the difference between existence and presence. While existence is independent, presence implies relationship. Nothing can simply be present; it must be present to something else.
For Chauvet, one of the best examples of this deadly dichotomy is Aquinas’s insistence that the Eucharist is “complete” or “perfected” at consecration. “The Eucharist is complete when the matter is consecrated, the other sacraments are complete only at the moment when the matter is being applied to the person who is receiving the sacrament.” For example, baptism is complete when water is poured on the person being baptized. The Eucharist, on the other hand, is complete at the moment of transubstantiation, long before it ever gets into the mouths of communicants. In short, Aquinas has removed the Church from the Eucharist. The Eucharistic body of Christ and the ecclesial body of Christ are starkly separated. By making transubstantiation the perfection of the Eucharist, it seems that Aquinas has chosen to emphasize Christ’s mere existence as an esse. The fact that the body and blood of Christ have come into existence is more important than the Church eating that body and blood. So, according to Chauvet, Aquinas has prioritized the relationship between the historical body of Christ and the eucharistic body of Christ. The deadly dichotomy has left its mark on Aquinas’s theology; transubstantiation leaves us with a mere existence of Christ, rather than Christ’s real presence for the Church.
II. Defending Aquinas: Christ Present as Spiritual Food
To respond to these criticisms, I will begin by agreeing with them. It is indeed unfortunate that Aquinas has chosen to say the Eucharist is “complete” at consecration. If the liturgy of the Eucharist is meant to represent Jesus’s eucharistic actions of take, bless, break, and give, then Aquinas has forgotten to include both breaking and giving (the actions concerned with the people Jesus is feeding) as essential parts of the Eucharist. However, I feel it would be incorrect to accuse Aquinas of separating the Eucharistic body of Christ from the ecclesial body. In fact, if we step back and look at his theology as a whole, we can see that the Eucharist finds its meaning in its relationship to the life of the Church.
Simply put, Aquinas’s theology is about Creation’s journey toward union with God. Aquinas calls humankind’s journey toward this goal ‘the spiritual life.’ All human beings are wayfarers (viatores) on our way to union with God. In this journey we are moved toward God by God’s grace which helps us live virtuously. Aquinas often uses the language of being turned toward God by grace that then helps us persevere in our journey. It is with reference to this graced journey that Aquinas begins his considerations of the Eucharist. When asked whether or not the Eucharist is a sacrament he says, “The Church’s sacraments are ordained for helping man in the spiritual life.” Baptism gives birth to our spiritual selves, confirmation helps us grow spiritually, and the Eucharist is our spiritual sustenance. Aquinas begins his eucharistic theology by defining the Eucharist as spiritual food for people on a spiritual journey. Immediately it should be clear that Aquinas has not forgotten about the relationship between the eucharistic body of Christ and the ecclesial body of Christ. In fact, it is his starting point.
I now return to the passage I quoted at the beginning of this essay: “Spiritual food changes man into itself.” Here, Aquinas is saying that the Eucharist is meant to turn human beings into Christ. However, it is important to note that this is not an individual transformation, but a communal transformation. The Eucharist forms the Church into the body of Christ. Another way of saying this is that the purpose of this sacrament is the “unity of the mystical [i.e. ecclesial] body of Christ.” The purpose of the Eucharist is to increase the unity of the Church. But how exactly does Aquinas envision this transformative relationship that exists between the eucharistic body of Christ and the ecclesial body of Christ? How does spiritual food change a community into Christ? The answer is one that we might expect: by being eaten.
In today’s modern world we are all aware of the importance of nutrition. We must be careful about what we eat. Our bodies need certain amounts of various nutrients and our metabolic processes convert that food into the energy we need to survive. However, this form of eating (the metabolic conversion of food to energy) is not how the Eucharist transforms us. It is a profound mistake to think that metabolizing a consecrated host (i.e. the substance of Christ’s body and blood) transforms us. Aquinas was quite careful when it came to describing how the Church eats the spiritual food of the Eucharist. He tells us that spiritual eating occurs when someone eats the Eucharist through faith and charity. Through spiritual eating a person is more deeply united to Christ and therefore the unity of the Church is deepened. It must be pointed out that physically consuming the consecrated host is not necessary for spiritual eating. Through belief in Christ (faith) and desire for union with him (charity), we spiritually eat the Eucharist, deepening our union with Christ.
There is nothing metabolic about eating spiritual food. In fact, spiritual eating is contrasted with sacramental eating. Sacramental eating is when a person eats the Eucharist without “securing its effects.” We are capable of consuming the Eucharist in a way that does not unite us to Christ. If someone approaches the Eucharist without the belief of faith or the desire of charity, although they consume the Eucharist, they cannot spiritually eat it.
This distinction between spiritual eating and sacramental eating is where I find my rebuttal to Chauvet’s critique. When Aquinas says that the Eucharist is complete at consecration, he has not simply ignored the relationship between the Eucharistic body of Christ and the Church. Rather, he has pinpointed the moment when spiritual eating occurs. Put differently, the Eucharist is complete when Christ becomes present as the object of the Church’s belief and desire. Consecration is not merely the moment of Christ’s substantial existence; it is the moment of Christ’s presence as spiritual food given to nourish a Church on a spiritual journey.
III. Friendship: The Real Presence of Christ
So, for Aquinas, the Eucharist is food with a purpose. It is spiritual food that exists to unite the ecclesial body of Christ in friendship (embodied koinonia).
In modern theology, it is common to hear criticisms of Aquinas’s eucharistic theology. Usually these criticisms are reacting to theological preoccupation with Aquinas’s theory of transubstantiation. I think Aquinas would agree with these criticisms. Theories about how Christ exists in the Eucharist should not distract from questions of why Christ becomes present in the Eucharist. When discussing the Eucharist we must always begin with its purpose (cf. 1 Cor 14:26). For Aquinas, the Eucharist is spiritual food that forms the Church more deeply into the living, bodily friendship that is the real presence of Christ.
When my students begin by asking about Eucharistic change (the how of the Eucharist), I give them a question in return: Why is Jesus present in the Eucharist? Once we begin to answer that question, we can return to the question of how he is present. When we eventually make our way back to the question of how, the metaphysical theories regarding changing substances is the least of their concern.
Dr. David Turnbloom teaches liturgy and sacramental theology at the University of Portland. This essay is based in part upon a piece previously published in Gottesdienst .
 According to Aquinas, there are actually two miracles that occur at the moment of consecration, but that is a topic for another article.
 For a full treatment of Aquinas’s Eucharistic theology see: David Farina Turnbloom, Speaking with Aquinas: A Conversation About Grace, Virtue, and the Eucharist, Liturgical Press: 2017.
 Summa Theologiae III.73.3.ad.2: “…alimentum spirituale convertit hominem in seipsum…”
 Henri de Lubac, Corpus Mysticum: The Eucharist and the Church in the Middle Ages, trans. Gemma Simmonds (London: SCM Press, 2006), 13.
 In fact, the importance of the ecclesial body was so central, that it was referred to as the corpus verum (the true body) while the eucharistic body was referred to as the corpus mysticum (the mystical body).
 cf. Louis Marie Chauvet, “The Broken Bread as Theological Figure of Eucharistic Presence,” in Sacramental Presence in a Postmodern Context, ed. L. Boeve and L. Leijssen (Leuven: Leuven University Press, 2001).
 Obviously, for something to be present it must also exist. This distinction is not meant to deny the role of existence. Rather, the distinction between existence (esse) and presence (adesse) is meant to help draw attention to the priorities in our theological inquiry
 ST III.73.1.ad.3
 ST II.II.24.4c
 ST III.73.1c
 ST III.73.3c
 ST III.80.1c