In Catholic theology, an Indulgence is the full or partial remission of temporal punishment due for sins which have already been forgiven. The indulgence is granted by the Catholic Church after the sinner has confessed and received absolution. The belief is that Indulgences draw on the Treasury of merit accumulated by Christ's superabandantly meritiorious sacrifice on the cross and the virtues and penances of the saints. They are granted for specific good works and prayers.
Indulgences replace the severe penances of the early Church. More exactly, they replaced the shortening of those penances that were allowed at the intercession of those imprisoned and those awaiting martyrdom for the faith.
The Church teaches that Indulgences do not forgive sins, but only relieve the temporal punishment due because of sins, and that a person is still required to have his grave sins absolved, ordinarily through the sacrament of Confession, to receive salvation.
Pope Paul VI revised the practical application of Indulgences by making it clear that repentance and faith are required not only for remission of eternal punishment from mortal sin but also for remission of temporal punishment for sin. Pope Paul VI wrote: "Indulgences cannot be gained without a sincere conversion of outlook and unity with God".