Five hundred years ago, the church in Western Europe was awash with cultural and scholarly forces that called for much-needed reform. Most of these forces flowed from the Renaissance, whose Christian scholars were weighing the contemporary church against what they found in the Bible and the writings of the early church fathers. The greatest of these scholars was Desiderius Erasmus of Rotterdam, who had in 1516 published a new critical edition of the Greek New Testament. It rapidly became a tool in the hands of reformers of all sorts. Prior to this, Erasmus had published new editions of many of the treatises of the church fathers and writings of his own critiquing contemporary Christianity in the name of a more biblical and more patristic faith. We cannot, for example, read Erasmus’ popular Handbook of the Militant Christian (1503) without seeing in it a vision of a reformed Christianity that trembles on the very verge of what we might call Protestant.
In the end, it fell not to Erasmus but to Martin Luther to catalyze these existing influences into an effective reform movement. Luther, a pastor-scholar of the Augustinian order of friars at the University of Wittenberg, had discovered in his own religious order the resources of an Augustinian theology of grace that he wanted to apply to the wider church. The prevailing theology taught in the Roman Catholic universities at that time (the so-called via moderna, or “modern way”) was anti-Augustinian, in that it placed all the emphasis on human free will and merit in securing salvation. To Luther, this was a doctrinal and pastoral disaster.
Traditionally, the start of the Reformation has been dated to Luther’s public protest on October 31, 1517, in his Ninety-Five Theses against the sale of indulgences. Simplifying a complex issue, indulgences were certificates of pardon authorized by the papacy that, it was thought, could shorten the time suffered in purgatory by the buyer or his deceased relatives. Although indulgences continue to be offered by the Roman church, it would be very hard to find even the most die-hard Roman Catholic who would now defend the horribly emotionally manipulative “indulgence preaching” of the Dominican friar Johann Tetzel, with his tasteless reassurances that anyone buying one of his indulgences would find mercy from God even if he had defiled the Virgin Mary. Only a degree less vulgar was Tetzel’s jingle “As soon as the coin in the money-box rings, a soul from purgatory springs!”
Had Luther’s protest against this monstrosity—initially made as a “Catholic reformer”—been better handled by the papacy, a very different story might have unfolded. We might all be praying to St. Martin Luther, patron of Roman Catholic reform. But Pope Leo X overreacted badly to Luther’s protest, bungled the whole affair, and succeeded in driving Luther, step by step, into an increasingly polemical stance, ultimately involving the basic issue of authority. By the time Luther stood as an accused heretic before the diet, or imperial assembly, at Worms in January 1521, he had rejected the supreme authority of the papacy within the church, affirming instead that Scripture possessed sole infallible authority for Christians. Later theologians would call this the “formal cause” of the Reformation: that which gives form, structure, and sense to Reformation teaching.
Although it did not figure at the Diet of Worms, a second principle—the “material cause” of the Reformation—soon became entangled with Luther’s movement for reform. This was justification by faith alone. When Luther and his fellow Reformers turned to Scripture as the church’s sole infallible authority, they found in its pages the teaching that sinners are justified (accepted as righteous by God) through faith alone in Jesus Christ alone. This was the gospel of the Reformation. Historians argue about when precisely Luther came to believe this; some place it as early as 1514, while others suggest a later date of 1519 (my preferred option). We do not find justification by faith in the Ninety-Five Theses, but we do find it in Luther’s watershed 1520 treatise On the Freedom of a Christian, where he expounds the doctrine with a lyrical, joyful eloquence.