n April 26, 1518, six months after the 95 Theses, Martin Luther presided at a disputation before his fellow Augustinian friars gathered in Heidelberg. Johann von Staupitz, the head of the order in Germany, wanted Luther given a fair hearing. Luther offered twenty-eight short theological theses, which he called “theological paradoxes,” to be tested against St. Paul and against St. Augustine, Paul’s “most trustworthy interpreter.”¹ The disputation caused little stir at the time, but among the friars who heard it were young men like Martin Bucer and Johannes Brenz, who later marked that day as the beginning of their support for Luther and his theology.²

In those theses Luther set out much of what the Reformation would teach: the distinction of law and gospel, the bondage of the will, and justification by faith rather than works. But the teaching most associated with Heidelberg today is what Luther called the theology of the cross.

The Seed in the 95 Theses

The idea was already present in the closing lines of the 95 Theses. Against the indulgence preachers, who promised the people a false security, Luther wrote:

Away with all those prophets who say to Christ’s people, “Peace, peace,” and there is no peace! May it go well for all of those prophets who say to Christ’s people, “Cross, cross,” and there is no cross!³ Martin Luther

Christians, he concluded, must follow Christ their head “through penalties, death, and hell,” and so enter heaven through many tribulations rather than through the false security of peace. At Heidelberg he took that conviction and made it a way of doing theology.

Two Kinds of Theologian

The heart of the disputation is theses 19 through 21. Luther does not speak, strictly, of two theologies but of two theologians, two ways of looking for God:

That person does not deserve to be called a theologian who looks upon the invisible things of God as though they were clearly perceptible in those things which have actually happened. He deserves to be called a theologian, however, who comprehends the visible and manifest things of God seen through suffering and the cross. A theologian of glory calls evil good and good evil. A theologian of the cross calls the thing what it actually is.⁴ Martin Luther

The theologian of glory reasons upward from what he can see. He looks at the works of God in the world, and at his own good works, and concludes from them what God must be like and how God may be pleased. Wisdom, power, success, and visible holiness are taken as signs of God’s favor. Luther did not deny that the “invisible things of God,” His goodness, wisdom, and justice, are real. He denied that knowing them in that way makes anyone wise or worthy (Romans 1:20–22).

The theologian of the cross looks where God has chosen to be found: in the weakness and folly of the crucified Christ (1 Corinthians 1:21–25). Because men misused the knowledge of God gained from His works, Luther wrote, God willed to be known in suffering, so that those who did not honor Him as He is revealed in His works might honor Him as He is hidden in His sufferings:

Now it is not sufficient for anyone, and it does him no good to recognize God in his glory and majesty, unless he recognizes him in the humility and shame of the cross.⁵ Martin Luther

Luther pointed to Philip, who asked, “Lord, show us the Father,” and was answered, “Whoever has seen me has seen the Father” (John 14:8–9). Philip wanted to see God somewhere else; Christ turned him back to Himself. “For this reason,” Luther concluded, “true theology and recognition of God are in the crucified Christ.”

That is why the theologian of glory calls things by the wrong names. “He who does not know Christ does not know God hidden in suffering. Therefore he prefers works to suffering, glory to the cross, strength to weakness, wisdom to folly, and, in general, good to evil.” Such people, Paul says, are “enemies of the cross of Christ” (Philippians 3:18). The theologian of the cross calls the cross good, because through it works are dethroned and the old Adam is crucified.⁶

God’s Alien Work and His Proper Work

The theology of the cross is not only a doctrine about how God is known. It is also a doctrine about how God saves. The first eighteen theses prepare for it. The law of God, though holy, cannot advance a man toward righteousness; human works that look attractive are “likely to be mortal sins”; the will after the fall is in bondage; and the person who thinks he can obtain grace “by doing what is in him adds sin to sin.”

Luther borrowed a phrase from Isaiah 28:21 to describe what God does. The law humbles, frightens, and kills, and this is God’s strange or “alien work.” But it serves His proper work, which is mercy:

Thus an action which is alien to God’s nature results in a deed belonging to his very nature: he makes a person a sinner so that he may make him righteous.⁷ Martin Luther

Luther insisted that this is not a counsel of despair but of hope. A sick man is not driven to death by being told how ill he is; he is driven to the physician. So the theses press on to the gospel: “The law says, ‘do this,’ and it is never done. Grace says, ‘believe in this,’ and everything is already done.”⁸ The theology of the cross is the doctrine of law and gospel seen at Golgotha.

The Love That Creates

The disputation closes with what many count among the most beautiful sentences Luther ever wrote:

The love of God does not find, but creates, that which is pleasing to it. The love of man comes into being through that which is pleasing to it.⁹ Martin Luther

Human love is drawn to what is already lovely. God’s love goes where there is nothing lovely and makes it so. It loves “sinners, evil persons, fools, and weaklings in order to make them righteous, good, wise, and strong.” Luther drew the conclusion plainly: “sinners are attractive because they are loved; they are not loved because they are attractive.” And he named the source of such love: “This is the love of the cross, born of the cross, which turns in the direction where it does not find good which it may enjoy, but where it may confer good upon the bad and needy person.”¹⁰

The Cross in the Christian Life

For Luther the cross was not one doctrine among others but the lens through which all theology must be read. In his lectures on the Psalms a year or so after Heidelberg he put it in four words: Crux sola est nostra theologia, “The cross alone is our theology.”¹¹

The Reformed tradition received the same conviction and pressed it into the shape of the Christian life. Calvin devoted a chapter of the Institutes to bearing the cross, following Christ’s call that every disciple must take up his cross (Matthew 16:24):

Those whom the Lord has chosen and honoured with his intercourse must prepare for a hard, laborious, troubled life, a life full of many and various kinds of evils. … Having begun this course with Christ the first-born, he continues it towards all his children.¹² John Calvin

The believer does not bear the cross to atone for sin or to earn favor; Christ’s cross is finished. He bears it because he is united to a crucified and risen Lord, and the members follow the Head. (See Union with Christ and Purity.)

Learned on the Anvil of Temptation

Timothy George observes that Luther was an existential theologian before he was anything else: concern with God was for him a matter of life and death, involving not merely the intellect but the whole person. Luther also thought in pairs, such as law and gospel, wrath and grace, and God hidden and God revealed, and George notes that he almost always chose to live with the tension rather than dissolve the paradox.¹³ The “theological paradoxes” of Heidelberg grew out of that habit of mind, and out of Luther’s own experience.

Luther’s word for the spiritual assaults that drove him was Anfechtung: not mere temptation, but dread, despair, and the sense of standing under God’s wrath with no way out. George shows that these assaults were not a passing phase of Luther’s youth but a recurring reality that defined his whole approach to theology. Luther said as much himself:

I did not learn my theology all at once, but I had to search deeper for it, where my temptations took me. … Not understanding, reading, or speculation, but living, nay, rather dying and being damned make a theologian.¹⁴ Martin Luther

The way out was the cross. In the years of his despair, Staupitz directed him to “the wounds of the most sweet Saviour,” and George treats that counsel as the first step in Luther’s developing doctrine of justification.¹⁵ The cross then shaped everything else:

It shaped how he read Scripture. As early as 1515 Luther warned that no one should lead the Bible according to his own inclinations, but “to the source, that is, the cross of Christ. Then he will surely strike the center.”¹⁶

It shaped how he counseled troubled souls. When Barbara Lisskirchen feared she was not among the elect, Luther would not let her pry into God’s hidden counsel. He sent her instead to the image of God’s Son as the mirror of His love: “Contemplate Christ given for us.” For Luther, George concludes, predestination could only be approached through the cross, through the wounds of Jesus to which Staupitz had first directed him.¹⁷

It shaped his doctrine of the church. Among the marks by which the true church may be known, Luther counted the “sacred cross,” the misfortune and persecution that God’s people suffer for His Word. In George’s words, “As there can be no theology of glory, so neither can there be any ecclesiology of glory.”¹⁸

Cautions and Counterarguments

It is not a cult of suffering. The theology of the cross does not teach that suffering is good in itself or that pain earns merit. Medieval piety had already made a ladder of self-chosen suffering, and Luther’s whole point was that no ladder reaches God. The cross in question is first Christ’s, not ours, and the suffering that matters is God’s humbling of the proud through His law and His providence.

It does not despise reason, creation, or the law. Luther guarded against that reading himself: “Yet that wisdom is not of itself evil, nor is the law to be evaded; but without the theology of the cross man misuses the best in the worst manner.”¹⁹ The gifts of God are good; the theologian of glory abuses them by taking the credit.

It does not deny God’s glory. The cross is not the absence of glory but the place where God’s glory is revealed in a form the world does not recognize. Christ endured the cross “for the joy that was set before him” (Hebrews 12:2), and the cross was followed by the empty tomb. A theology of the cross that forgets the resurrection is not Luther’s.

It is not a license for gloom or cynicism. To call a thing what it actually is includes calling grace good, forgiveness real, and the Christian blessed. The theologian of the cross is not the one who expects the worst, but the one who has stopped expecting anything from himself and expects everything from God.

Why It Still Matters

Every generation has its theologians of glory. Some promise health and wealth to those with enough faith. Some measure faithfulness by numbers, influence, and visible success. Some offer a Christ who makes people feel strong rather than one who makes them confess they are weak. In each case the visible is taken as proof of the invisible, and the cross is quietly set aside as a stage to be passed rather than the place where God is known.

The Reformers would not allow it. “We preach Christ crucified, a stumbling block to Jews and folly to Gentiles, but to those who are called, both Jews and Greeks, Christ the power of God and the wisdom of God” (1 Corinthians 1:23–24). The Lord who told Paul, “My power is made perfect in weakness” (2 Corinthians 12:9), still meets His people in the same place: not where they look strong, but where they are brought low and lifted up by grace.

Related

• Law and Gospel
• Justification by Faith Alone
• The Bondage of the Will
• Union with Christ
• Purity
• Martin Luther
• Martin Bucer

Theological Recoveries Next: Union with Christ

Sources

1. Martin Luther, Heidelberg Disputation (1518), preface to the theological theses, trans. Harold J. Grimm, in Luther’s Works, vol. 31, Career of the Reformer I (Philadelphia: Fortress, 1957), 39–70. Text available at BookofConcord.org. ↩
2. Timothy J. Wengert, introductions to volume 1 and to the 95 Theses, in The Annotated Luther, vol. 1, The Roots of Reform, ed. Timothy J. Wengert (Minneapolis: Fortress, 2015). ↩
3. Martin Luther, Disputation for Clarifying the Power of Indulgences [95 Theses] (1517), theses 92–95, trans. Timothy J. Wengert, in The Annotated Luther, vol. 1. ↩
4. Luther, Heidelberg Disputation, theses 19–21, in Luther’s Works 31:40. ↩
5. Luther, Heidelberg Disputation, proof of thesis 20, in Luther’s Works 31:52–53. ↩
6. Luther, Heidelberg Disputation, proof of thesis 21, in Luther’s Works 31:53. ↩
7. Luther, Heidelberg Disputation, proof of thesis 16, in Luther’s Works 31:50–51; see also the proof of thesis 4 on God’s “alien work” (Isaiah 28:21). ↩
8. Luther, Heidelberg Disputation, proof of thesis 17 and thesis 26, in Luther’s Works 31:51, 41. ↩
9. Luther, Heidelberg Disputation, thesis 28, in Luther’s Works 31:41. ↩
10. Luther, Heidelberg Disputation, proof of thesis 28, in Luther’s Works 31:57. ↩
11. Martin Luther, Operationes in Psalmos (1519–21), on Psalm 5, in D. Martin Luthers Werke (Weimar edition) 5:176. ↩
12. John Calvin, Institutes of the Christian Religion, 3.8.1, trans. Henry Beveridge (Edinburgh: Calvin Translation Society, 1845). ↩
13. Timothy George, “Yearning for Grace: Martin Luther,” in Theology of the Reformers, rev. ed. (Nashville: B&H Academic, 2013), ch. 3, section “Luther as Theologian.” ↩
14. Martin Luther, quoted in George, “Yearning for Grace,” section “Anfechtung.” ↩
15. George, “Yearning for Grace,” section “From Simul to Semper: Justification by Faith Alone.” ↩
16. Martin Luther (1515), quoted in George, “Yearning for Grace,” section “Christ in the Crib: The Meaning of Sola Scriptura.” ↩
17. Martin Luther, letter to Barbara Lisskirchen, quoted in George, “Yearning for Grace,” section “Let God Be God: Predestination.” ↩
18. George, “Yearning for Grace,” section “The Priority of the Gospel,” drawing on Luther’s seven marks of the church in On the Councils and the Church (1539). ↩
19. Luther, Heidelberg Disputation, thesis 24, in Luther’s Works 31:41. ↩

Further Reading

• Timothy George, Theology of the Reformers, rev. ed. (Nashville: B&H Academic, 2013), ch. 3, “Yearning for Grace: Martin Luther”
• Gerhard O. Forde, On Being a Theologian of the Cross: Reflections on Luther’s Heidelberg Disputation, 1518 (Grand Rapids: Eerdmans, 1997)
• Alister E. McGrath, Luther’s Theology of the Cross (Oxford: Blackwell, 1985)
• Carl R. Trueman, Luther on the Christian Life: Cross and Freedom (Wheaton: Crossway, 2015)