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Justification by Faith


The Protestant Reformation began when a Catholic monk rediscovered a Catholic doctrine in a Catholic book.


The monk, of course, was Luther; the doctrine was justification by faith; and the book was the Bible.  One of the tragic ironies of Christian history is that the deepest split in the history of the Church, and the one that has occasioned the most persecution, hatred, and bloody wars on both sides, from the Peasants' War of Luther's day through the Thirty Years' War, which claimed a larger percentage of the population of many parts of central Europe than any other war in history, including the two world wars, to the present-day agony in Northern Ireland — this split between Protestant and Catholic originated in a misunderstanding.  And to this day many Catholics and many Protestants still do not realize that fact. 

Luther's story is well known.  Passionate, impetuous, demanding, sensitive, and pessimistic in temperament, Luther had never been able to find inner peace.  He could not overcome his sense of guilt despite all his good works, prayers, penances, and alms.  His confessor advised him to read Romans.  No more historically momentous advice was ever given by a confessor.  In Romans Luther discovered the simple bombshell truth that God had forgiven his sins freely, not because of Luther's works in Germany but because of Christ's work on Calvary.  That discovery freed Luther's spirit and ignited a fire that swept over Europe.  The watchword of the Reformation became Saint Paul's summary of the gospel: "The just (justified, saved) shall live [have eternal life] by faith [in Christ]" (Rom 1: 17)

Where then do good works come in?  In Christian Liberty, Luther explains that after the great liberation about faith — that we are saved by faith in Christ's work, not by our works — comes a great liberation about works: they need not be done slavishly, to buy our way into heaven, to pile up merits or Brownie points with God, but can be done freely and spontaneously and naturally, out of gratitude to God — not to get to heaven but because heaven has already gotten to us.  Thus they can be done for the sake of our neighbor, not for our own sake, to purchase salvation.  And this is winsome.  No one wants to be loved as someone else's good deed for the day. 

The origin of the Reformation is often said to be Luther's act of nailing ninety-five theses against the sale of indulgences to the door of the church in Wittenberg.  This event is celebrated as Reformation Day (October 31, 1517).  Luther's decision to go public was occasioned by the scandal of Tetzel, a Dominican monk who shamelessly peddled forgiveness of sins for a fee.  He even had a singing commercial: "Sobald das Geld im Kasten klingt,/Die Seele aus dem Fegfeuer springt!" ("As soon as the money clinks in the casket, the soul springs free from the fires of purgatory!") The story was told of the thief who asked Tetzel whether he could buy forgiveness for all his future sins as well as his past sins.  Tetzel said yes, but it would cost him a thousand gold pieces.  The thief paid the money, took the indulgence, and then stole back the money from Tetzel!

But the scandal of selling indulgences was only the catalyst, not the cause, of the Reformation.  The Church soon cleaned up its act and forbade the sale of indulgences at the Council of Trent, agreeing with Luther on this point.  But one does not split the Church over a practice; one splits the Church over a doctrine, for the Church can change its practice but never its doctrine.  To change a practice, one stays in the Church; to change a doctrine, one must start a new Church. 

Luther eventually came to reject many Catholic doctrines that he thought he could not find in Scripture.  But only one justified his bold words before the Diet of Worms, which condemned him: "Here I stand.  I cannot do otherwise.  God help me." The doctrine was justification by faith.  The justification of Luther's faith, he thought, was the doctrine of justification by faith. 

For everything is at stake here.  The question is nothing less than how to get to heaven.  Luther thought the Catholic Church was teaching not only heresy (heretics always call orthodoxy heresy, by the way) but another religion, another way of salvation, "another gospel" (Gal 1:6).  That's about as serious a charge as you can imagine.  We need to examine this charge very carefully to justify the surprising claim that the fundamental dispute between Protestants and Catholics was due to a misunderstanding.

It certainly doesn't look like a misunderstanding.  It looks like a flat-out contradiction: the Catholic Church taught that we are saved by faith and good works, while Luther taught that we are saved by faith alone (sola fide).  But appearances may be deceiving. 

For one thing, even if the two sides did disagree about the relationship between faith and works, they both agreed (1) that faith is absolutely necessary for salvation and (2) that we are absolutely commanded by God to do good works.  Both these two points are unmistakably clear in Scripture. 

For another thing, the terms of the dispute are ambiguous or used in two different senses.  When terms are ambiguous, the two sides may really disagree when they seem to agree because they agree only on the word, not the concept.  Or the two sides may really agree when they seem to disagree because they agree on the concept but not the word.  The latter holds true here. 

I remember vividly the thrill of discovery when, as a young Protestant at Calvin College, I read Saint Thomas Aquinas and the Council of Trent on justification.  I did not find what I had been told I would find, "another gospel" of do-it-yourself salvation by works, but a clear and forceful statement that we can do nothing without God's grace, and that this grace, accepted by faith, is what saves us.

When Luther taught that we are saved by faith alone, he meant by salvation only the initial step, justification, being put right with God.  But when Trent said we are saved by good works as well as faith, they meant by salvation the whole process by which God brings us to our eternal destiny and that process includes repentance, faith, hope, and charity, the works of love. 

The word faith was also used in two different senses.  Luther used it in the broad sense of the person's acceptance of God's offer of salvation.  It included repentance, faith, hope, and charity.  This is the sense Saint Paul uses in Romans.  But in 1 Corinthians 13, Paul uses it in a more specific sense, as just one of the three theological virtues, with hope and charity added to it.  In this narrower sense faith alone is not sufficient for salvation, for hope and charity must be present also.  That is the sense used by the old Baltimore Catechism too: faith is "an act of the intellect, prompted by the will, by which we believe what has been revealed on the grounds of the authority of God, who revealed it." 

This "faith", though prompted by the will, is an act of the intellect.  Though necessary for salvation, it is not sufficient.  Even the devils have this faith, as Saint James writes: "Do you believe that there is only one God?  Good! The demons also believe — and tremble with fear" (James 2: 19).  That is why James says, "it is by his actions that a person is put right with God, and not by his faith alone" (James 2:24).  Luther, however, called James' epistle "an epistle of straw."  He did not understand James' point (applied to Abraham's faith): "Can't you see?  His faith and his action worked together; his faith was made perfect through his actions" (James 2:2 2). 

Faith is the root, the necessary beginning.  Hope is the stem, the energy that makes the plant grow.  Love is the fruit, the flower, the visible product, the bottom line.  The plant of our new life in Christ is one; the life of God comes into us by faith, through us by hope, and out of us by the works of love.  That is clearly the biblical view, and when Protestants and Catholics who know and believe the Bible discuss the issue sincerely, it is amazing how quickly and easily they come to understand and agree with each other on this, the fundamental divisive issue.  Try it some time with your Protestant friend. 

But many Catholics to this day have not learned the Catholic and biblical doctrine.  They think we are saved by good intentions or being nice or sincere or trying a little harder or doing a sufficient number of good deeds.  Over the past twenty-five years I have asked hundreds of Catholic college students the question: If you should die tonight and God asks you why he should let you into heaven, what would you answer?  The vast majority of them simply do not know the right answer to this, the most important of all questions, the very essence of Christianity.  They usually do not even mention Jesus!

Until we Catholics know the foundation, Protestants are not going to listen to us when we try to teach them about the upper stories of the building.  Perhaps God allows the Protestant/Catholic division to persist not only because Protestants have abandoned many precious truths taught by the Church but also because many Catholics have never been taught the most precious truth of all, that salvation is a free gift of grace, accepted by faith.  I remember vividly the thrill of discovery when, as a young Protestant at Calvin College, I read Saint Thomas Aquinas and the Council of Trent on justification.  I did not find what I had been told I would find, "another gospel" of do-it-yourself salvation by works, but a clear and forceful statement that we can do nothing without God's grace, and that this grace, accepted by faith, is what saves us. 

The split of the Protestant Reformation began when a Catholic discovered a Catholic doctrine in a Catholic book.  It can end only when both Protestants and Catholics do the same thing today and understand what they are doing: discovering a Catholic doctrine in a Catholic book.

This is Meaghen Gonzalez, Editor of CERC. I hope you appreciated this piece. We curate these articles especially for believers like you.

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Kreeft, Peter. "Justification by Faith." Chapter 44 in Fundamentals of the Faith. (San Francisco: Ignatius Press, 1988), 277-281.

Reprinted by permission of Ignatius Press. All rights reserved. Fundamentals of the Faith - ISBN 0-89870-202-X.

The Author

kreeft1kreeftPeter Kreeft, Ph.D., is a professor of philosophy at Boston College.  He is the author of many books (over forty and counting) including: Ask Peter Kreeft: The 100 Most Interesting Questions He's Ever Been AskedAncient PhilosophersMedieval PhilosophersModern PhilosophersContemporary Philosophers, Forty Reasons I Am a Catholic, Doors in the Walls of the World: Signs of Transcendence in the Human Story, Forty Reasons I Am a CatholicYou Can Understand the Bible, Fundamentals of the Faith, The Journey: A Spiritual Roadmap for Modern Pilgrims, Prayer: The Great Conversation: Straight Answers to Tough Questions About Prayer,  Love Is Stronger Than Death, Philosophy 101 by Socrates: An Introduction to Philosophy Via Plato's Apology, A Pocket Guide to the Meaning of Life, Prayer for Beginnersand Before I Go: Letters to Our Children About What Really Matters. Peter Kreeft in on the Advisory Board of the Catholic Education Resource Center.

Copyright © 2014 Peter Kreeft

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