SO GREAT A SACRAMENT
Saint Thomas Aquinas and the Eucharist
Because Christ our Redeemer said that it was truly his body that he was offering under the species [or “appearance”] of bread, it has always been the conviction of the Church of God, and this holy Council now declares again, that by the consecration of the bread and wine there takes place a change of the whole substance of the bread into the substance of the body of Christ our Lord and of the whole substance of the wine into the substance of his blood. This change the holy Catholic Church has fittingly and properly called transubstantiation.[1]
So decreed the Council of Trent in 1551, reaffirming language first promulgated dogmatically at the Fourth Lateran Council in 1215. In view of the profound appreciation for the Eucharist as a mystery that we saw in St Ignatius of Antioch and St Ephrem the Syrian, what are we to make of all this philosophical-sounding talk of “species,” “substance,” and “transubstantiation”? For help in approaching this question, I would like to turn to the great Dominican St Thomas Aquinas (c. 1225–1274), widely recognized as the most nuanced and penetrating expositor of the doctrine of transubstantiation.
Thomas belongs to a tradition of Christian theology that arose in the twelfth century, known as “Scholasticism.” Through careful, disciplined study of Scripture, the Fathers, and philosophy, medieval Scholastics sought a comprehensive integration of human reason and divine revelation. But Scholasticism in general and Aquinas in particular are sometimes accused of failing to respect Christian revelation’s character as an awe-inspiring mystery. First, objectively, by bringing revelation under rational scrutiny, Scholasticism is thought to empty out its mysterious character, pridefully attempting fully to comprehend the divine. To borrow Ephrem’s words, it illegitimately “pries” or “investigates.” Second, subjectively, Scholasticism is lifeless and dull. Its cautious, plodding, almost mathematical procedure appears utterly devoid of the pastoral passion of Ignatius’s letters or the poetic radiance of Ephrem’s madrashe.
There is little point in denying that some Scholastics have fallen into one or both of these deficiencies. But are they intrinsic to Scholasticism? Is fides quarens intellectum (faith seeking understanding) incompatible with fides adorans mysterium (faith adoring the mystery)? Is it impossible to love the Lord with all our heart and with all our mind? I would like to suggest that Thomas’s Eucharistic teaching shows that it is not. To the contrary, when done well, Scholastic theology can enhance our appreciation of the divine mystery precisely as mystery, and help us to grow in loving awe of the mystery.
The impression that Aquinas was all head and no heart, a cold intellectual with a colder prayer life, should be dispelled. It is true that the superficial reader of his Summa theologiae will not find there any surplus of warm devotional language. This would have been inappropriate to the work’s genre, and Thomas was disciplined and restrained. Other works, however—above all his liturgical poetry and sermons—betray a heart on fire with love for Christ.
Thomas’s reputation among his contemporaries and near-contemporaries bears witness to the mystical dimension of his faith. We saw in the last installment of this series that St Ephrem loved to meditate on the wound in Christ’s side as our access to Paradise. Similarly, according to Thomas’s early biographer Bernard Gui (d. 1331), Thomas the Dominican was like Thomas the Apostle “in entering the abyss of the side of Christ … entering as one invited, and therein searching out and expressing the mysteries contained there.”[2] Aquinas himself speaks of Christ’s side as a gateway to Paradise. He observes that, in the Vulgate, John 19:34 does not say that the soldier “wounded” Christ’s side but that he “opened his side.” Why? “Because through [his] side the door to eternal life is opened to us.” This is the “open door” through which John gains vision into heavenly, apocalyptic reality (Rev. 4:1).[3] In an exposition of Psalm 22, Aquinas teaches that this aperture is also the key to Scripture: “The phrase ‘heart of Christ’ can refer to Sacred Scripture, which makes known his heart, closed before the Passion, as the Scripture was obscure. But the Scripture has been opened since the Passion.…”[4]
Among the “mysteries” Thomas sought out and expressed, none was dearer to him than the Eucharist. The complex and subtle treatise on the Eucharist found in the Third Part of the Summa theologiae, questions 73–83, might seem clinical and emotionless. But the liturgical poetry Thomas composed for the Feast of Corpus Christi is filled with expressions of faith, piety, and awe. The hymn Sacris solemniis begins the morning by calling for great rejoicing to accompany the feast. Lauda Sion, chanted at Mass before the Gospel, insists that Christ’s gift of the Eucharist surpasses our utmost efforts to praise him. Pange lingua gloriosi, the hymn for Vespers, exhorts the faithful: Tantum ergo Sacramentum / veneremur cernui—literally, “So great a Sacrament, therefore, let us venerate, bowing down.”
If Thomas’s last word, so to speak, on the Eucharist is a call to prostrate adoration, then why all the metaphysical acrobatics? Gui records the friar’s heartfelt prayer before his final Holy Communion, which included these words: “O price of my redemption and food for my pilgrimage, I receive you. For your love I have studied and toiled and kept vigil.”[5] Aquinas himself clearly thought his fervent piety and sober intellectual labor were connected. But how?
One way to answer is perhaps most apparent in Thomas’s Summa contra Gentiles. After a brief introduction to the Eucharist, Thomas begins his discussion in earnest by recalling that “some of the disciples were troubled” at Jesus’ words, “For my flesh is true food, and my blood is true drink” (John 6:55). “This is a hard saying;” they responded, “who can listen to it?” (John 6:60). “Likewise,” writes Aquinas, “heretics have arisen also against the Church’s teaching by denying its truth. For they say that the body and blood of Christ are not in this Sacrament really, but only symbolically.” Such people take Christ’s words at the Last Supper to be figurative, like Paul’s when he says in 1 Corinthians 10:4 that “the Rock was Christ.”[6] Aquinas then reels off a series of “difficulties” that lead to such a view. One thing after another “seems impossible” or “absurd.” He concludes this chapter modestly: “These things, therefore, and others like them, are why the teaching of Christ and the Church concerning this Sacrament seems hard.”[7]
Rather than dismissing the objections, Thomas takes them seriously. In the next five chapters, he patiently addresses each one. Here the concept of transubstantiation functions, not as an explanation of how the change of bread and wine to body and blood occurs, but as a way of naming, very precisely, what it is that happens: all the physical properties of bread and wine remain, yet the realities that underlie them become, by the power of God, Christ’s body and blood. This sophisticated framework allows Thomas to show that Jesus’ teaching as understood and handed on by the Church violates neither reason nor biblical revelation. He closes this section, again, modestly: “These difficulties, then, having been removed, it is clear that what the Church’s Tradition holds concerning the Sacrament of the Altar contains nothing impossible for God, who can do all things.”[8] Far from seeking to exhaust or replace the mystery of the Eucharist, Thomas’s teaching on transubstantiation preserves the mystery, clearing the way for the doubtful to place their faith in the Word of God, “who can do all things.”
Much more remains to be said, of course. In the interest of space, I simply offer recommendations of three recent books that amply demonstrate the ongoing fruitfulness of Thomas’s Eucharistic thought.
Reinhard Hütter’s Aquinas on Transubstantiation: The Real Presence of Christ in the Eucharist (Washington, DC: Catholic University of America Press, 2019) is a slim but very dense volume that holds up Aquinas’s Eucharistic reflection as a model for how Christian theology should be done. Hütter guides the reader through Thomas’s complex metaphysical reflections while carefully keeping in view their purpose, which is to aid believers in listening attentively to biblical revelation, and thereby to be drawn into deeper friendship with Christ.
Jan-Heiner Tück’s A Gift of Presence: The Theology and Poetry of the Eucharist in Thomas Aquinas originally appeared in German, but it is now available in an English translation by the Augustine Institute’s own Scott Hefelfinger (Washington, DC: Catholic University of America Press, 2018). Tück sets Aquinas’s “mind,” represented by his theological treatments of the Eucharist, side-by-side with his “heart,” shown in his Eucharistic poetry. Tück beautifully shows not only their compatibility but their deep complementarity.
Brett Salkeld’s Transubstantiation: Theology, History, and Christian Unity (Grand Rapids, MI: Baker Academic, 2019) is remarkable for its ambitious and intriguing ecumenical proposals. Salkeld argues that, when understood according to Thomas’s articulation of it, the Catholic doctrine of transubstantiation should prove largely acceptable to traditional Lutheran and Reformed Christians. Not only that—Salkeld even suggests ways in which transubstantiation might mediate differences between the two Protestant traditions!
May St Thomas continue to inspire us all to listen to God’s Word with reverent faith, and to love him with our hearts and our minds.
This is the third of a five part series on the Eucharist by Professor Sehorn. The first two essays in the series can be seen here and here.
[1] Quoted at CCC 1376.
[2] Quoted at Paul Murray, OP, Aquinas at Prayer: The Bible, Mysticism and Poetry (New York: Bloomsbury, 2013), 8.
[3] Commentary on John, ch. 19, lect. 5.
[4] Exposition of Psalm 21, 11; quoted at CCC 112.
[5] Quoted at Murray, 32.
[6] Summa contra Gentiles 4.62.1.
[7] Summa contra Gentiles 4.62.16.
[8] Summa contra Gentiles 4.68.1.
