What reform did Martin Luther seek within the Catholic Church?

Martin Luther is best known for his role in initiating the Protestant Reformation, primarily through his criticism of specific practices within the Catholic Church, most notably the sale of indulgences. Indulgences were payments made to the Church that were believed to reduce punishment for sins. Luther argued that this practice, along with other corrupt activities and the Church's focus on wealth, undermined the true essence of Christianity and the necessity of faith for salvation. His 95 Theses, which he famously nailed to the church door in Wittenberg, called for reforms aimed at returning to a more scripture-centered practice of faith and emphasized salvation through faith alone rather than monetary transactions. This approach is what fundamentally drove his reformation efforts rather than seeking to abolish the Church entirely or aiming for a union of all Christian denominations.