Today in History—October 31: A Reformation Ignites

In 1517 a Roman Catholic monk and theologian named Martin Luther did something that would eventually split Western Christianity.

According to tradition, Luther nailed his Ninety-five Theses to the door of the Castle Church in Wittenberg, Germany, on this day. Whether that dramatic moment actually happened is disputed, but we know he did send his theses to Archbishop Albert of Mainz that day.

Luther wasn’t trying to start a religious revolution. He was an Augustinian priest and professor hoping to spark an academic debate about so-called “indulgences,” which reduced the temporal punishment associated with sin. He was particularly angered by the extravagant claims of Johann Tetzel, a local friar who was selling indulgences to help finance the rebuilding of St. Peter’s Basilica in Rome (Albert was Tetzel’s superior).

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Written in Latin, the theses were relatively tentative in tone, consisting of 95 short propositions—most just a sentence or two.

But the printing press got involved, and things escalated.

Although Luther had not intended his work for the broader public, his theses were soon translated into German, printed, and distributed. His criticism of the wealthy papacy collecting money from poor Germans struck a chord. What began as an academic dispute became a public controversy, and questions about indulgences soon expanded into larger debates about salvation, Scripture, and papal authority.

In 1520 Pope Leo X demanded that Luther recant statements from his writings. In response, Luther publicly burned the papal bull threatening excommunication (and was indeed promptly excommunicated).

At the Diet of Worms in 1521, he again refused to back down unless convinced by Scripture or reason. Declared an outlaw, he went into hiding at Wartburg Castle, where he began translating the New Testament into German—a vernacular Bible being another bold challenge to the religious establishment.

The upheaval Luther helped unleash became the Protestant Reformation, permanently reshaping Christianity and European history. October 31 is now celebrated by Lutherans and other Protestants as Reformation Day. Not a bad legacy for an academic debate.