From .............. Our Sunday Visitor's
Roman Catholic CD ROM Encyclopedia
Remission of the temporal punishments for sins, and therefore the giving of satisfaction owed God for one's sin. Indulgences are granted either after the sacrament of Penance or by perfect contrition. Indulgences are either plenary [when all punishments are remitted] or partial [when only part of that punishment is remitted]. Plenary indulgences demand that one be free of all venial sin, but partial indulgences do not require this.
Partial indulgences remit the amount of temporal punishment that would be remitted in the ancient Church by performances of penances for the designated period of time. Indulgences can only be gained for oneself or for those in purgatory, but not for other living human beings.
Indulgences are derived from the treasure of merits of the saints, from Christ Himself or from His Mother.
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