Despite the fact that he was developing a new and distinctive theology, until 1517, Luther remained a relatively minor figure—an undistinguished theology professor at a tiny university tucked away in Saxony. But this would soon change dramatically. Luther would be instantly, and unexpectedly, catapulted into the international spotlight and would, by 1520, be one of the most famous men in Europe.

The Indulgence Controversy

The act that launched Luther's career as a church reformer was relatively small—or at least it seemed to be at the time. As a university professor, one of Luther's duties was to engage occasionally in public debates—called disputations—about theological or philosophical topics. The professor would draft a series of theses that he would be willing to defend, post these theses publicly, and then take on whoever wanted to argue against him in a public debate. These debates were intended to clarify disputed issues, to deepen the intellect and rhetorical skills of participants, and to some degree to entertain and education the audience, which would typically be made up of university students. Proposing such a debate, even on a controversial topic, would have raised few eyebrows. So when, in 1517, Luther posted a list of theses critical of the church's teachings on indulgences, he did not expect to ignite a churchwide controversy.

What is an indulgence?

Luther's 95 Thesesopposed the sale of indulgences. These were an outgrowth of the sacrament of penance. Late medieval theology held that a person in a state of sin could not enter heaven. This was inconvenient because all people—even deeply religious ones—tended to continue to sin regularly. Fortunately, the church had a process by which sinners could return to a state of grace after sinning. The sinners must first repent and confess their sins to a priest. After this, sinners must perform some act of penance. Only after these steps had been accomplished could sin be atoned for and a sinner be reconciled to God. If a person died in a state of sin, without having performed the proper penance, he or she could not go directly to heaven.