Martin Luther was honest, diligent, compassionate, but most of all he was courageous. He lived a life dedicated to loving others and lived what he preached. He consistently followed through with his word which made him very credible and a leader that the people respected.
During this time in the 16th century, upper clergy had become like secular rulers instead of religious authority. The church owned massive amounts of land and was part of the feudal system. Immorality had become rife in the higher clergy with simony (pay-offs) and non-celibacy becoming the norm.
According to Catholic theology at the time, if one sinned you could repent and be given the sacrament of penance. While the blame for the sin is gone the sin is not erased and you must still be punished for it through temporal punishment on earth or in purgatory. You can, however, lessen the amount of punishment by performing acts of merits. You can also be spiritually assigned merit by the church via its treasury of merit. This is typically done through prayers. The transfer of merit is an indulgence.
In Luther’s time indulgences were horribly being abused. Johann Ttzel, a Dominican friar, was given authority by the Pope to sell indulgences in order to build St. Peter’s Basilica in the Vatican. Luther witnessed Johann selling indulgences and the words Johann used to sell them were deplorable, telling people that they wouldn’t go to heaven without them or their loved ones would be saddled with their sins when they died if they didn’t pay. Basically, Johann said whatever it took to induce fear in people to make them pay
References: Covey, S. R. (1992). Principle-centered leadership. (p. 101=102). New York: Free Press. Thomasson, C. (Writer) (2003). Luther [Web]. Retrieved from http://www.youtube.com/watch?v=xc6Ci_V23oE