Final answer:
The term for a paper granting pardon from sin is an indulgence, used historically by the Catholic Church as a way to reduce or cancel time in purgatory in exchange for charitable works or donations.
Step-by-step explanation:
The term for a paper that supposedly granted pardon from the punishment of sins is an indulgence. In historical practice, the Catholic Church would acknowledge a donation or charitable work with an indulgence. It represented a way to reduce or even cancel the required time in purgatory, where souls atoned for their sins before being allowed into heaven. The pope, who was believed to have access to a store of merit from Jesus and the saints, could allot this merit in the form of an indulgence.
These practices were controversial and were among the issues that Martin Luther addressed in his 95 Theses in 1517. Luther argued that indulgences undermined the importance of genuine repentance and contrition for one's sins. Thesis 36 states that "Any truly repentant Christian has a right to full remission of penalty and guilt, even without indulgence letters." The sale of indulgences was seen as a corruption within the Church, ultimately contributing to the Protestant Reformation.