Forgiveness of sin by God through the Church frees one from the eternal punishment, but there is also the temporal punishment due for sin. Thus, as a corollary to the power of forgiving sin, the Church has also the power to dispense to the faithful from the treasury of the merits of Christ and the saints the emission of the temporal punishment when the penitent has fulfilled certain conditions.

What an indulgence is in Catholic tradition is thus summed up by the New Code of Canon Law: "An indulgence is the remission in the sight of God of the temporal punishment due for sins, the guilt of which has already been forgiven. A member of Christ's faithful who is properly disposed and who fulfills certain specific conditions, may gain an indulgence by the help of the Church which, as the minister of redemption, authoritatively dispenses and applies the treasury of the merits of Christ and the saints." (Canon 992).

An indulgence may be partial when the temporal punishment is partially remitted, or plenary when fully remitted. Indulgences can be gained also for the souls of the dead. To be capable of gaining indulgences, one has to be a baptized person, not excommunicated, and in the state of grace, apart from fulfilling the other prescribed conditions. (Cans. 993,994,996).

We know from history that indulgences were offered by the Church to encourage enlistment in the Crusades. This practice grew further when those who went on pilgrimages were granted indulgences. The practice arose too of the faithful offering monetary contributions to gain indulgences, a practice similar to the offer of stipends for Masses. There was the 'great indulgence' of 1516 to 1518, preached to collect funds for the rebuilding of St Peter's Church in Rome. This monetary aspect, which has been wrongly and cynically labelled as 'the sale of indulgences'. Was much criticized at the Reformation. Luther not only vehemently decried the practice but also rejected indulgences altogether.

The Council of Trent reaffirmed the Church's teaching on indulgences and also took stringent measures to correct abuses and remove occasion for scandals.

As a result of discussions at the Second Vatican council, Pope Paul VI clarified the Church's position relating to indulgences, which is reflected in the Canons referred to above.