This is the third of a 5-part series that will blog through Trevin Wax’s choices for Christianity’s Most Important Theologians. We will explore each to show why Trevin and others find these figures so influential. The first posts were on Athanasius and Augustine.

Thomas Aquinas is a theologian some Protestants love to hate, others love to love, but he is always respected. Though he was rarely condemned outright by early Protestants, there has always been a certain uneasiness about his teachings as they connect to his ideas on grace, justification, sacraments, and the church. They blow hot and cold on his borrowing of Aristotle, too, which was always Luther’s major complaint.

But there is a tension within any attempt to outright reject Aquinas: it’s not part of the Protestant heritage.

Within a generation of Luther’s reformation, most Protestant training centers for pastors, including Wittenberg, used at least some of Aquinas’s writings in their curriculum, even if they did not embrace all of his teachings. This is true in modern seminaries and bible colleges, too. Those interested today, for example, in arguments for God’s existence always turn to Aquinas’ ‘5 Ways,’ or 5 methods of argument, for coming to a rational conclusion that God exists (though never fully apart from faith, as Aquinas would point out).

Our opinion of Aquinas, then, forms a microcosm of the Reformation’s use of medieval theology: Protestants do not reject everything, but they have grave concerns about some of its teachings.

It would be helpful then to give a few thoughts on why Aquinas is so influential to land in a Top 5 list of historical figures.

Aquinas’s Life and Times

Thomas Aquinas (1225-1274) was born with a silver spoon in his mouth, as he was the son of the Duke of Aquino in Italy. In keeping with medieval names, ‘Aquinas’ is not actually his last name, but a reference to the landed estate of his family in Aquino (for this reason it’s not called ‘Aquinoism’ but ‘Thomism’). Thomas would have been thoroughly educated to read and write and think, and all the opportunities for his life would have been unthinkable to an average peasant. His second cousin, in fact, was the Holy Roman Emperor at the time, which means he was not only born into money but into power.

Thomas’s first rebellious act was to reject the luxurious church job his family had planned for him. His father had wanted a priestly office for his son at the wealthy monastery at Monte Cassino—the first such monastery in Europe, though it had since grown lazy in its monastic rigor. The monastery was also politically and culturally powerful, so his father wanted an ‘inside man’ there.

Thomas told his father he was instead joining the Dominicans—at which point his brothers kidnapped him, locked him in his room, tempted him with a prostitute, and vowed not to let him leave—until his mother chose to leave a window open for him one evening in order to escape.

Joining the Dominicans was a bit like joining the Jesus Freaks in the 1960s: they were a radical expression of the faith that made church leaders nervous. The Dominicans believed ‘radical’ ideas such as the notion that Jesus was not a wealthy aristocrat living in luxury, but rather a poor man without a place to rest his head. The Dominican order wanted to live this type of radical life and were known as one of the new ‘begging orders,’ since the monks would hold no wealth at all and live on hand-outs from others.

After gaining his freedom, Thomas travelled eventually to Paris, the intellectual heart of Europe, and there began to study theology and the Bible.

Theology in Aquinas’s Day

Aquinas was not liked by his student contemporaries either. In a tone that must have been bullying, his classmates called him the ‘Dumb Ox’ for his lumbering gait and the slowness of his thinking. Maybe they just thought it was funny to make fun of the noble son who now begged for his food. In either case, he was to become the most influential scholastic mind of the entire medieval period, shaping discussions on theology and philosophy so profoundly, the Catholic Church would officially name his works as their own.

The central issue driving scholasticism was the problem of faith and reason. The question can be said this way: what is the primary source of our knowledge of theology, and to what extent can we use tools like reason to explore our faith? It’s a debate present from the beginning of Christian theology and continues today, but in Aquinas’s day the issue was critical.

By Aquinas’s day, scholastics had more or less wound up on mutually exclusive positions. On the one hand are those we can call the Concealed view: those who believe doctrines such as the Trinity or the divinity of Christ are utterly foreign to any natural mode of thinking, so they must only be acknowledged as mystery and never studied as one would philosophy. Today these would be folks who say we must never attempt to discuss the Trinity because it is simply a mystery.

The other side in Aquinas’s day we can call Compatiblists: those who believe that if there is anything in doctrine that is illogical or lacks verification in philosophy, then we need to apply our minds to find a better solution or description. At its extreme, these would be folks who would rather abandon the language of a historic doctrine if it could not meet their standard for rational thinking.

In Aquinass’ world, these issues were on everyone’s mind, having been the preoccupation for men like Anselm, Abelard, and Bernard of Clairvaux. It was Aquinass’ answer to this problem that became one of the great answers to rational theology: Grace perfects Nature.

Grace Perfects Nature

Aquinas solved the problem of faith and reason, in essence, by denying there even was a fundamental problem, so long as reason and faith were understood in their proper places. Reason, he argued, is a gift of God and established in creation as a virtue for all men and women. Reason is therefore to be understood as a gift of nature—meaning it is a natural capacity in all of us.

The problem to deal with is the corruption of sin that leaves our reason clouded. Aquinas answered that the nature of grace in a Christian is not to override reason but to work at recovering reason to its proper place. So grace perfects nature, it does not destroy it. Our reasoning is fallen into sin and we are capable of wickedness and foolishness. But God works by his Spirit to put us back in our right minds—like the Gerasene demoniac restored to his right mind and at the feet of Jesus.

So to go back to the example of the Trinity: Aquinas will argue that the doctrine of God’s triune nature is something that is revealed and established by faith, not reason. However, once established by faith it can be the subject of reflection and study, not in an effort to base the doctrine on reason but rather to use our natural minds to deepen our appreciation of the wonder of this truth. Careful distinctions and philosophical language are appropriate in trinitarian reflections, not because they build up to the doctrine but because we have reason in its proper place.

Aquinas and Protestantism

To appreciate Aquinas’s contributions to theology does not mean that Protestants are entirely happy with each of his teachings. He taught things about justification, for example, that were thoroughly medieval, namely that grace infuses into us at baptism and it is then our responsibility to cooperate with grace for our final justification. His teachings on the sacraments were also influential in the development of Catholic views of transubstantiation. We could go on, but there is not a short list of things people question in Aquinas’s teachings.

When we stop to appreciate Aquinas as an historical figure, then, it is not because we love everything we see. But the long Protestant engagement with Aquinas on things like faith and reason and other doctrines is not weakened by our profound disagreement on other matters.

Still, we can nevertheless look back—as did John Calvin, Philip Melanchthon, Martin Bucer, and even Luther in his quieter moments—and respect the heroic efforts of a theologian who has shaped our thinking for nearly 800 years.