Review of The Trinitarian Christology of St Thomas Aquinas

Legge, O.P., Dominic. The Trinitarian Christology of St Thomas Aquinas. Oxford, UK: Oxford University Press, 2017, pp. 261, $27.99, paperback.

The Trinitarian Christology of St Thomas Aquinas is a work that reorients modern scholarship’s approach to understanding how Aquinas’s Christology is intrinsically Trinitarian.

Dominic Legge, O.P. serves as the Director of the Thomistic Institute and is an Associate Professor of Dogmatic Theology at the Pontifical Faculty of the Immaculate Conception in Washington, D.C. Besides his J.D. from Yale Law School, he also holds a Ph.L. from the School of Philosophy of the Catholic University of America and a S.T.D. from the University of Fribourg in Switzerland. During his time in Switzerland, he studied under Gilles Emery, O.P. whom he cites often throughout The Trinitarian Christology of St Thomas Aquinas. 

Legge explains the reason to undertake the study of Thomas Aquinas’s (1225-1274) Trinitarian Christology is because modern scholarship has misunderstood Aquinas, such as Karl Rahner and Hans Urs von Balthasar. Rahner and Urs von Balthasar, among others, have accused Aquinas of highlighting the hypostatic union to the detriment of the doctrine of the Trinity and the Holy Spirit. Legge shows how these accusations are unwarranted. He explains, “The better we grasp how Aquinas’s Christology is intrinsically Trinitarian, the better we will discern the unity of his thought and the intelligible order he discerns in the whole dispensation of salvation, as it emerges from the Trinity and leads us back to the Trinity” (p. 4).

He successfully shows how Aquinas’s Christology is intrinsically Trinitarian by dividing the book into three parts. In part one, Legge builds the theological foundation by examining the eternal processions of God and how they are expressed visibly and invisibly in time through the divine missions. The incarnate Christ is the pathway to reveal the Trinity to man and the pathway to return man to the Trinity. In other words, Christ’s divine mission as the God-man is how the Father initiates salvation and the Spirit applies salvation. In part two, Legge narrows more specifically on the incarnate Christ who assumes a human nature. Aquinas uses four descriptors when examining the incarnation of the eternal Son of God: Word, Son, Image, and Author of Sanctification (pp. 61-102). The reason Legge specifically looks at these four descriptors is to further prove his thesis that Aquinas’s Christology is Trinitarian because they point to the other two divine persons. Christ is the Word of the Father, the Son of the Father, the image of the Father, and the author of sanctification who gives the sanctifying Holy Spirit. This section also examines how hypostatic union terminates in the person of the Son, who is from the Father. In part three, Legge focuses more on the Spirit and how the person of Christ, in his divine mission, works by and in the Spirit. In this section, Legge explains that Christ as man receives the invisible divine mission of the Holy Spirit. Meaning, Christ as man received all the blessings and graces needed to work and see the beatific vision so that he knows the divine will as man.

The intended audience for this book are academics who are interested in studying the doctrine of the Trinity and/or the historical influence Thomas Aquinas had in theological thought. This book is technical and the reader does need a certain amount of theological knowledge to follow Legge’s argument.

Legge is successful in showing how Aquinas’s Christology is intrinsically Trinitarian. This work examines an important research question because many other theologians have misunderstood Aquinas on this issue, such as Karl Rahner and Hans Urs von Balthasar, according to Legge (p. 3). Aquinas does make Christology central in his theological endeavors; however, by making Christ the centerpiece he shows the rest of the Trinity through Christ and how man can return to God in salvation through Christ. The Father, Son, and Spirit are always working inseparably in each divine mission, visible or invisible. While the incarnation terminates in the Son, the Father is revealed and the Spirit sanctifies. Legge explains this reality well when he explains, “Christ’s humanity and his human actions not only reveal, but in revealing also lead us to the Father – which is another way of speaking about the incarnation as the visible mission of the Son” (p. 119).

Throughout this book Legge also clearly brings out Aquinas’s Trinitarian dynamic motion in revealing the Trinity by the Trinity in order to allow man to return to the Trinity by the Trinity, which allows the careful reader to easily see Aquinas’s influence on many others such as the seventeenth-century theologian John Owen (1616-1683). In other words, Legge plainly explains that Aquinas taught that the Father reveals himself through the Son by the Spirit to man so man can return to the Father by the Spirit through the Son. In this return route Legge explains, “Aquinas does not conceive of this as a linear movement, and even less a one-way journey; it is part of a perfect circular movement . . . such that everything returns to that from which it proceeded as a principle, as if returning to its end” (p. 223). Legge proceeds to then explain how the Holy Spirit draws mankind to God through Christ. The language of returning back to God through the Trinity, the principle end, is seen throughout the book. Owen’s well-known treatise, Communion with the Father, Son, and Holy Ghost, looks to this concept. Owen explains, “Our communion, then, with God consisteth in his communication of himself unto us, with our returnal unto him of that which he requireth and accepteth, flowing from that union which is Jesus Christ we have with him” (John Owen, The Works of John Owen, ed., William Goold, 16 vols. [Carlisle, PA: The Banner of Truth Trust, 2009], 2:8-9). Like Aquinas, Owen understood this “returnal unto him” to be done according to what Owen called, the “heavenly directory,” a concept he derived from Ephesians 2:18 (Owen, Works, 2:269). The heavenly directory is to worship the Father by the Spirit through the Son. In fact, Legge points out that Aquinas first looks to Ephesians 2:18 to explain, “As the divine missions make present in a new way and reveal the Trinitarian processions, they are likewise the vectors of our return to the Triune God, with the Father ‘the ultimate person to whom we return’” (p. 120).

The Trinitarian Christology of St Thomas Aquinas is a work that reorients modern scholarship’s approach to understanding how Aquinas’s Christology is intrinsically Trinitarian. They are not divorced according to Aquinas. The intended audience for this book are academics who are interested in studying the doctrine of the Trinity and/or the historical influence Thomas Aquinas had in theological thought. This book is technical and the reader does need a certain amount of theological knowledge to follow Legge’s argument. For example, there are no definitions given to common doctrines such as the beatific vision, divine appropriation, inseparable operations, etc. However, Legge builds a nice theological foundation for his reader in the first two chapters on divine missions that sets the pace for the rest of the book. Overall, it is an excellent study on the Trinity and how Aquinas articulates this mysterious doctrine.