The Reformation presents the historian with an acute instance of the general problem of scholarly interpretation—namely, whether events are shaped primarily by individuals or by the net of historical circumstances enmeshing them. The phenomenon that became the Protestant Reformation is unthinkable without the sense of mission and compelling personality of Martin Luther. But in social and intellectual conditions less conducive to drastic change, Luther’s voice would have gone unheard and his actions been forgotten. Among the preconditions—which are the deeper causes of the Reformation—the following stand out: (1) Everyone agreed that the Roman Catholic church was in need of correction. The lack of spirituality in high places, the blatant fiscalism, of which the unrestrained hawking of indulgences—the actual trigger of the Reformation—was a galling example, and the embroilment in political affairs all were symptoms of corruption long overdue for purgation. While the church continued to be accepted as the only legitimate mediator of divine grace, denunciations of its abuses, perceived or actual, became more strident in the decades before 1517. (2) A subtle change, moreover, had been occurring in people’s religious needs and expectations, leading to demands for a more personal experience of the divine. Failing to meet this aspiration, the church was widely, if diffusely, rebuked for its unresponsiveness. (3) More focused criticism came from the Christian humanists, an influential group of scholars bent on restoring the fundamental texts of Western Christianity. Led by Desiderius Erasmus, the most renowned biblical scholar of the time, these men held the Catholic church up to the spiritual ideals for which it claimed to stand and, finding it wanting, set the principle of Evangelicalism against the church’s secularized ambitions. (4) Still more fatefully, by 1500 the church had come under attack from European rulers whose administrative, legal, and financial hegemony could not be completed in their respective states without domination of the ecclesiastical sector. In the empire, as elsewhere, the trend in ecclesiastical politics was toward state churches (Landeskirchen), in which governments, using “reform” as a pretext, gradually gained, while church authorities lost, a large measure of control over clerical properties, personnel, and functions. The Reformation was the culmination of this process, which, in the empire, took place in nearly all princely territories and in most independent cities, where governments brought the administration of the church under political direction. (5) In Germany this development was facilitated by an ancient feudal custom entitling a landlord to extend “protection” to churches located on his estates. Over this “owner’s church” (Eigenkirche) he enjoyed the right of patronage, allowing him to appoint incumbents and manage properties. In the course of extending their sovereignty, territorial princes took over this right to patronage and fashioned of it the legal basis on which, in the Reformation, they assumed full control over the administration of the church. (6) In every segment of German society, but particularly among the poor, voices were being raised against injustice and exploitation. Wide disparities in income and discriminatory laws in cities as well as the deteriorating standard of living of small peasants and agricultural laborers caused riots and uprisings, which by the early 1500s had become endemic.

These, then, were the forces driving events toward a crisis. In the first decade of the 16th century they coalesced into a powerful surge of religious, social, and political agitation, for which “reform” (of church and society) was the code word. Ironically, Luther, who was to channel this agitation into the Reformation, had, until his emergence as a national figure in the 1520s, nothing to do with it. For him one issue alone mattered: the imperative of faith. His personal path to the Reformation was an inner search for religious truth, to which his conscience was his guide.

When he wrote his Ninety-five Theses against indulgences in October 1517, Luther was an Augustinian friar, a preacher in the Saxon city of Wittenberg, and a theology professor at the university founded there in 1502 by the elector of Saxony, Frederick III, called “the Wise.” His ambitious father had pushed him toward a career in law, but in 1505 the fervently devout Martin entered a monastic house. His order, that of the Augustinian eremites, was a strict reform congregation dedicated to prayer, study, and the ascetic life. Deeply troubled by the question of justification—of how a human being, a sinner, may be justified (saved) in God’s sight—Luther found no comfort in monastic routine and turned to an exploration of the sources of Christian doctrine, notably St. Paul and St. Augustine. His intellectual promise having been recognized, he was sent by his order to study theology at Erfurt and Wittenberg. He was awarded a doctorate in 1512 and commenced his teaching of the Bible in Wittenberg that same year. According to his own account, it was during his close reading of Paul’s Epistle to the Romans, while preparing to give a course of lectures on that text, that he discovered what struck him as the solution to the problem posed by the huge gap between human sin and divine grace. Justification is not earned as a reward for human effort through good works (a position Luther now attributed to a misguided and misguiding Roman church). To the contrary, human beings are justified without any merit of their own by God’s freely given and prevenient (i.e., coming before any worthy human deeds) grace, through faith, which is a gift of God. This is the meaning Luther found in the crucial passage in Romans 1:17: “For in it [i.e., the Gospel] the righteousness of God is revealed through faith for faith: as it is written, ‘He who through faith is righteous shall live.’” “Righteousness”—justitia in Latin—does not refer, Luther believed, to God’s activity as judge but to the justifying righteous condition he effects in the human sinner, a condition expressing itself as faith. The momentous consequences of this theological insight, which Luther appears to have taken as a unique discovery but which had in fact been espoused by a score of theologians before him, were not then apparent to him. They asserted themselves powerfully, however, once he began to lecture and preach on the—for him—paramount themes of salvation by faith alone (sola fide) and exclusive reliance on scripture (sola scriptura). It was the indulgence controversy of October 1517 that brought it all into the open.

Few other issues could so clearly have exposed the gulf that separated this ardent friar from an urbane and pragmatic church. The indulgence offered in Saxony in 1517 had its origin in two purely financial arrangements. First, Popes Julius II and Leo X needed funds for rebuilding St. Peter’s Basilica in Rome; second, Bishop Albert of Hohenzollern, forced to buy papal dispensations in order to gain the archbishoprics of Mainz and Halberstadt, agreed to promote indulgences in his domains, half the income from which was to go to Rome, the other half to him and his bankers. For Luther, the issue turned not so much on the outrageous venality of this deal as on the indulgence itself. Truly contrite sinners do not desire relief through an indulgence (which is a remission of the penance, or temporal punishment, that the sinner would otherwise owe following absolution); they crave penance. This is the gist of Luther’s argument in the Ninety-five Theses, which he sent to his ecclesiastical superiors to persuade them to abandon the indulgence sale. (The story that he nailed a copy of the theses to the door of the Castle Church in Wittenberg may be the invention of a later time. See Researcher’s Note: The posting of the theses.)

Luther intended no defiance with this action. He intervened as a priest on behalf of his flock and as a conscientious theologian against a corrupting church. But the public reaction to the theses (he had written them in Latin, but they were soon translated and printed) made it evident that he had touched a nerve. Encouraged by expressions of support and goaded by opponents, Luther became more outspoken, harsher in his criticism of the church, and more focused in his attacks on the papacy. By 1520 he was well on his way to becoming the spokesman for Germany’s grievances against Rome. A pamphlet he published that year, Address to the Christian Nobility of the German Nation, urged the empire’s secular rulers to reform a church that would not set its own house in order. Popes and prelates are not sacrosanct, he argued; they may be brought to justice. As every Christian can read the Bible for himself, papal claims to interpretive authority are a vain boast. Luther prodded the German princes to consider the state of the church and to reform it for the sake of the faith. In this way Luther drew out, albeit reluctantly, the full consequences of his principle of “salvation by faith alone.” No church was needed to act as God’s agent; grace was available without mediation. No priest, not even the pope, has special powers, for, so Luther argued, all human beings are priests, made so by their faith. It is scarcely surprising that a bull of excommunication against him (Exsurge domine) issued from Rome in June 1520.