Answer:
It showed people the corruptness of the churches in the era. People realized that the church was used mostly for profit, and that selling indulgences would never "forgive them of their sins" as sellers claimed. It caused Martin Luther to publicly put down the church, leading to a new branch of Protestantism called Lutheranism. The selling of indulgences would ultimately split up the church in clashing ideals and thoughts on access to the Bible, as well as how it should be interpreted.