How did the printing press help spread Martin Luther’s criticism of indulgences?

The printing press was instrumental in transforming Martin Luther’s Ninety-five Theses from a localized academic dispute into a widespread controversy that challenged papal policy regarding indulgences.1

By enabling the rapid mass production of Luther’s ideas, the printing press allowed his criticisms to circulate quickly throughout Germany. Luther became one of the most effective early pamphleteers, using short, printed booklets to inflame popular opinion against the Roman Catholic Church and the pope. This technology effectively bypassed traditional channels of ecclesiastical control, turning a theological disagreement into a broad movement that contributed to the Protestant Reformation.13

As the volume and intensity of these printed works grew, the church responded with increasingly harsh censorship, eventually establishing the Index Librorum Prohibitorum to suppress such writings.2