Theopedia

Thomas Aquinas

Overview

Thomas Aquinas (1225-1274) was an Italian Dominican friar and scholastic theologian whose Summa Theologiae became the central text of Roman Catholic theology and philosophy.1 Reformed theology rejects his doctrine of grace and merit,2 but Protestant scholastics such as Francis Turretin drew directly on his arguments for divine simplicity and analogical predication in constructing their own doctrine of God.3

Life and Ministry

Aquinas was born around 1225 at Roccasecca, the castle of his father Landulf, count of Aquino, in the kingdom of Naples.1 He received his early schooling at the abbey of Monte Cassino before studying for six years at the University of Naples.1 In his seventeenth year he joined the Dominican order, over his family’s opposition; the dispute was resolved only through papal intervention by Innocent IV.1

He studied under Albertus Magnus, following him from Cologne to Paris around 1245 for three years of further training.1 He went on to teach at Paris, then at Cologne from 1248 as a second lecturer, and later at Naples from 1272.1 A century and a half later, the Reformed scholastic Petrus van Mastricht’s own theological education still included direct study of the Summa Theologiae.4 Aquinas died on 7 March 1274 at the Cistercian monastery of Fossa Nuova, having fallen ill while traveling to the Second Council of Lyons.1

Theological Contribution

Grace, Predestination, and Merit

Aquinas’s doctrine of grace, set out in the Prima Secundae of the Summa Theologiae (Questions 109-114), rests on an unconditional doctrine of predestination: God’s love for the elect creates their worthiness rather than responding to merit he foresees in them.5 Grace is necessary at every stage of salvation, not only to justify but even to prepare the soul to receive the grace that justifies, and to persevere in it afterward.6 Justification itself Aquinas defines as a four-stage movement of the soul, the infusion of grace, faith turning toward God, the will turning away from sin, and the forgiveness of sins, that nonetheless “happens in an instant.”7

Once a person stands in a state of grace, Aquinas holds that they can merit further grace and eternal life. He distinguishes two kinds of merit: condign merit, a strict equivalence between the work and its reward, insofar as the work proceeds from the grace of the Holy Spirit; and congruent merit, proportionate to human capacity but not strictly equivalent, insofar as the same work proceeds from free choice.8 O’Kelley summarizes the resulting pattern in Aquinas’s own text: “There is no dichotomy between grace and merit; merit is itself the result of grace… However, this grace does not preclude a doctrine of human merit and a form of works-righteousness.”9 The sacraments, particularly baptism and penance, are the instrumental means by which this grace is applied to the individual believer.10

Analogical Predication and the Doctrine of God

Aquinas holds that the words Scripture and theology apply to God and to creatures, such as “wise” or “good,” are neither univocal (meaning exactly the same in both cases) nor purely equivocal (sharing nothing but the word itself), but analogical. Asking in the Summa whether such terms are used univocally of God and creatures, he answers that they cannot be, because “God is more distant from creatures than any creatures are from each other… [so] much less can anything be predicated univocally of God and creatures.”11 This grammar of analogy underwrites Aquinas’s wider doctrine of God, including divine simplicity, the teaching that God is not composed of parts and is identical with his own attributes.12

Historical Significance

Francis Turretin, in constructing his own account of divine simplicity and analogical predication, engages Aquinas’s text directly (citing, among other passages, Summa Theologiae I.3.5, I.11.3, and I.14.5) even while reframing the argument.3 Richard Muller describes this move as a shift “away from the large-scale use of philosophical categories and a definition of theological truth and certainty exclusive of the philosophical categories of the day,” yielding, in Turretin’s hands, “a more biblically grounded defense of the classical doctrine of God.”13

Bavinck states the Reformed objection to Rome’s “bridge of meritoriousness by which we in some sense deserve our final destiny,” the ex condigno merit Aquinas’s own text supplies: it “fails to do justice to grace,” turning final salvation into “a fitting, worthy, proportionate reward for work done” rather than a purely gracious gift.2

Aquinas was canonized in 1323 by Pope John XXII, and in 1567 Pope Pius V ranked his feast day with those of Ambrose, Augustine, Jerome, and Gregory the Great, the four great Latin fathers.1 The Encyclopaedia Britannica’s own 1911 assessment held that “no theologian save Augustine has had an equal influence on the theological thought and language of the Western Church.”1 The Summa Theologiae remains the founding text of Thomism, the philosophical-theological school that takes his name.

Related Doctrines

External Links

References

  1. “Aquinas, Thomas,” in The Encyclopaedia Britannica, 11th ed. (Cambridge: Cambridge University Press, 1911), a public-domain reference used here for biographical facts (dates, education, teaching posts, canonization) not otherwise found in the secondary sources cited elsewhere in this article. ↩ ↩2 ↩3 ↩4 ↩5 ↩6 ↩7 ↩8 ↩9

  2. Herman Bavinck, Reformed Dogmatics: Abridged in One Volume, ed. John Bolt (Grand Rapids: Baker Academic, 2011), chap. 11, “The Image of God.” ↩ ↩2

  3. Alex Charles Tibbott, “Turretin and Classical Theism,” in “De Impassibilitate Et Satisfactione: An Examination of the Methodological Implications of Trinitarian Classical Theism for the Doctrine of the Atonement” (PhD diss., The Southern Baptist Theological Seminary, 2024), 96. ↩ ↩2

  4. “Life and Work,” in Theoretical-Practical Theology, vol. 1, by Petrus van Mastricht, ed. Joel R. Beeke, trans. Todd M. Rester (Grand Rapids: Reformation Heritage Books, 2018), 5. ↩

  5. Aaron Thomas O’Kelley, “Grace and Merit in Late Medieval Theology,” in “A Historical-Theological Critique of the New Perspective on Paul” (PhD diss., The Southern Baptist Theological Seminary, 2010), 37. ↩

  6. O’Kelley, “Grace and Merit,” 39. ↩

  7. O’Kelley, “Grace and Merit,” 41. ↩

  8. O’Kelley, “Grace and Merit,” 42-43. ↩

  9. O’Kelley, “Grace and Merit,” 45. ↩

  10. O’Kelley, “Grace and Merit,” 43-44. ↩

  11. Darron Thomas Chapman, “Thomas Aquinas and the Definition of Person in the Summa Theologiae,” in “The Concept of Person in Christian Theology: An Exposition and Defense of a Classical Boethian/Thomistic Definition of Person” (PhD diss., The Southern Baptist Theological Seminary, 2026), 95, quoting Thomas Aquinas, Summa Theologiae, ed. John Mortensen and Enrique Alarcón, trans. Laurence Shapcote (Lander, WY: The Aquinas Institute for the Study of Sacred Doctrine, 2012), I, q. 13, art. 5, s.c. ↩

  12. Chapman, “Thomas Aquinas and the Definition of Person,” 95-96. ↩

  13. Tibbott, “Turretin and Classical Theism,” 97, quoting Richard A. Muller, Post-Reformation Reformed Dogmatics, 3:119. ↩