what is ninety-five theses?
It is a list of propositions for an academic disputation based on the disputation on the Power and Efficacy of Indulgences.
Ninety-five Theses
The Ninety-five Theses or Disputation on the Power and Efficacy of Indulgences is a list of propositions for an academic disputation written in 1517 by Martin Luther, 
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Ninety-five Theses [SEP] Introduction
The Ninety-five Theses or Disputation on the Power and Efficacy of Indulgences is a list of propositions for an academic disputation written in 1517 by Martin Luther, professor of moral theology at the University of Wittenberg, Germany. They advance Luther's positions against what he saw as the abuse of the practice of clergy selling plenary indulgences, which were certificates believed to reduce the temporal punishment in purgatory for sins committed by the purchasers or their loved ones. In the "Theses", Luther claimed that the required by Christ in order for sins to be forgiven involves inner spiritual repentance rather than merely external sacramental confession.