Martin Luther played a pivotal role in the religious transformation in Europe by initiating the Protestant Reformation in the early 16th century. His posting of the 95 Theses in 1517 challenged the practices of the Catholic Church, particularly the sale of indulgences. Luther advocated for salvation through faith alone and the authority of scripture over church tradition. His translation of the Bible into German made religious texts accessible to the laity, empowering individuals to interpret scriptures themselves. This movement led to the fragmentation of Christianity, the rise of various Protestant denominations, and significant social and political changes in Europe. Luther's actions ultimately reshaped Western religious thought.