Luther: the theology of the cross and justification

A monk before a righteous God

The events of the Reformation are told in the Reformed Faith course's lesson The story of the Reformation. This lesson follows what Martin Luther (1483–1546) taught, and why. His theology grew from one question: how can a sinner stand before a holy God?

In 1505 Luther entered the Augustinian friary at Erfurt and gave himself to prayer, fasting and confession with unusual zeal. Yet he later wrote that, though he lived as a monk without reproach, he felt himself before God a sinner with a deeply troubled conscience. As professor of Bible at the young university of Wittenberg he was haunted by Paul's phrase ‘the righteousness of God’. He had been taught to read it as the justice by which God, being righteous, punishes the unrighteous, and he could not love such a God.

Day and night he pressed on the verse and its context:

For the gospel reveals the righteousness of God that comes by faith from start to finish, just as it is written: “The righteous will live by faith.”

Romans 1:17

At last he saw that the righteousness revealed in the gospel is not one God demands of us but one he gives: the righteousness by which a merciful God justifies us through faith. In the preface to his collected Latin writings (1545) he said that he felt born again, as though he had gone through open gates into paradise. Afterwards, he added, he read Augustine's On the Spirit and the Letter and found that Augustine too had understood God's righteousness as the one with which God clothes us when he justifies us Luther, Preface to the Latin Writings. When this happened, and whether it was a single moment or a slow dawning over several years, scholars still debate.

John Wesley read the verse the same way. Paul, he wrote, "when treating of justification, means hereby the righteousness of faith; therefore called the righteousness of God, because God found out and prepared, reveals and gives, approves and crowns it" Wesley. Wesley himself received his assurance in 1738 while someone was reading Luther's preface to Romans aloud (Wesley). The doctrine itself is taught in the doctrine course's lesson Faith and justification.

The theology of glory and the theology of the cross

In October 1517 Luther put forward ninety-five theses for a debate on the power of indulgences Luther, The Ninety-five Theses. The first says that when our Lord Jesus Christ called us to repent, he willed the whole life of believers to be one of repentance; the sixty-second, that the true treasure of the church is the most holy gospel of the glory and grace of God. The famous picture of Luther nailing the theses to the door of the Castle Church in Wittenberg rests on later reports, chiefly Melanchthon's, written after Luther's death; Luther himself never mentions it, and historians are divided on whether it happened. What is certain is that on 31 October he sent the theses with a letter to the Archbishop of Mainz.

In April 1518, at a meeting of his Augustinian order in Heidelberg, Luther set out the heart of his theology Luther, The Heidelberg Disputation. He contrasted two kinds of theologian. The theologian of glory tries to see through created things and human works to God's invisible power and wisdom; he prefers works to suffering, glory to the cross, strength to weakness. The theologian of the cross knows that God has chosen to make himself known hidden in suffering and the cross. The first, Luther wrote, calls evil good and good evil; the second calls a thing what it is.

He learned this from Paul:

Jews demand signs and Greeks search for wisdom, but we preach Christ crucified, a stumbling block to Jews and foolishness to Gentiles, but to those who are called, both Jews and Greeks, Christ the power of God and the wisdom of God. For the foolishness of God is wiser than man’s wisdom, and the weakness of God is stronger than man’s strength.

1 Corinthians 1:22-25

The theology of the cross is not a love of suffering for its own sake. It means looking for God not where we expect to find him, in power, success and our own achievements, but where he has given himself: in Christ crucified. That is why it comforts sinners who have nothing to bring and believers who suffer. The last of the Heidelberg theological theses, the twenty-eighth, sums it up: human love comes into being when it finds something lovable, but the love of God does not find what is lovable to it; it creates it.

The freedom faith gives

In 1520 Luther wrote a stream of treatises. The Freedom of a Christian opens with two propositions which, in an old English translation, run: "A Christian man is the most free lord of all, and subject to none; a Christian man is the most dutiful servant of all, and subject to every one" Luther, The Freedom of a Christian. Both come from Paul, Luther said, who wrote, "Though I am free of obligation to anyone, I make myself a slave to everyone" (1 Corinthians 9:19).

What makes a Christian free is faith, not works. The commandments, Luther explained, teach what is good but give no power to do it; they show us our helplessness, for "the law merely brings awareness of sin" (Romans 3:20). The promises of the gospel give freely in Christ what the commandments demand. Telling law and gospel apart became a pillar of Lutheran theology.

Faith also unites the soul with Christ, as a bride is joined to her bridegroom. In marriage all that each has becomes common, so the soul's sin and death become Christ's, and Christ's righteousness and life become the soul's. This has come to be called the ‘happy exchange’. Paul puts it this way: "God made Him who knew no sin to be sin on our behalf, so that in Him we might become the righteousness of God" (2 Corinthians 5:21).

So the believer is, in Luther's phrase, at once righteous and a sinner (simul iustus et peccator): wholly righteous before God in Christ's righteousness, yet still fighting sin within Luther, Lectures on Galatians. This is no licence to sin. Freed by faith, the Christian serves the neighbour gladly and for nothing, giving himself, as Luther put it, as a Christ to his neighbour. Matthew Henry answered the old objection: "It is no new prejudice, though a most unjust one, that the doctrine of justification by faith alone, tends to encourage people in sin" Matthew Henry.

That service happens in ordinary life. In To the Christian Nobility of the German Nation (1520) Luther taught that all the baptised are priests Luther, To the Christian Nobility, as Peter calls believers "a royal priesthood" (1 Peter 2:9). Pastors differ from other Christians in office, not in standing before God, and the shoemaker, the smith and the farmer each have a calling in which to serve their neighbours. Kitchen, field and workshop, not the cloister alone, became places to serve God.

Debate, confession and legacy

At the Diet of Worms in 1521, ordered to recant before the Emperor Charles V, Luther answered that unless he was convinced by Scripture or by plain reason he could not, for his conscience was captive to the word of God. The words ‘Here I stand; I can do no other’ appear in early printed accounts, but we cannot be sure he spoke them. Outlawed, he was hidden in the Wartburg castle, where he translated the New Testament into German.

In 1524 the humanist Erasmus published On Free Will. Scripture's many commands and appeals, he argued, imply some small power in us to respond to grace, and on questions too deep to settle we should speak with restraint. His concern for moral responsibility and the peace of the church was sincere. Luther replied in The Bondage of the Will (1525): in the matter of salvation the human will is bound by sin, and only God's grace can free it Luther, The Bondage of the Will. He thanked Erasmus for going to the heart of the matter instead of side issues such as the papacy and indulgences. Reformed and Wesleyan Christians would later answer the question of grace and the will in different ways.

In 1530 the Augsburg Confession, written by Luther's colleague Philip Melanchthon, was presented to Charles V. Its fourth article confesses that we are justified freely for Christ's sake through faith, not by our own strength, merits or works The Augsburg Confession. With Luther's Small Catechism (1529) it became the standard of the Lutheran churches, first in Germany and Scandinavia and then across the world.

Luther's faults must be told honestly. He often used coarse and abusive language against his opponents, and in the Peasants' War of 1525 he urged the princes to crush the rebels by force. Worst of all, in writings of 1543 he called for synagogues to be burned and Jews to be driven out, though twenty years earlier he had urged kindness toward them. These writings were later used by antisemites, and many Lutheran churches today have formally rejected them. Luther would have us honour not himself but the Christ he pointed to.

The story continues beyond 1900. In 1999 the Lutheran World Federation and the Catholic Church, in their Joint Declaration on the Doctrine of Justification, affirmed together that God accepts sinners by grace alone, through faith in what Christ has done and not for any merit of theirs, and declared that the sixteenth-century condemnations do not apply to the teaching each side set out there. Differences remain Joint Declaration on the Doctrine of Justification.

What Luther leaves us is comfort. God shows himself not in our achievements but in Christ crucified, and he is the God "who justifies the ungodly" (Romans 4:5). For more, see What is justification?; for how the Reformed churches carried this confession forward, see the Reformed Faith course's lesson Grace alone, faith alone.

Practice