In the early days of the Church it sometimes happened that a person was condemned to endure a severe penance; but if he went to a Christian friend who happened to be suffering for the faith in prison, and this friend interceded for the penitent with the bishop, offering his own sufferings for the benefit of the penitent, the bishop would accept them and grant absolution to the penitent, This was the first kind of indulgence granted by the Church. It differed in many details from the type of indulgence with which we are familiar today; but the principal feature of an indulgence was present namely, the offering of the satisfaction, of one member of the Church for another through the ministry,of the Church. Down through the centuries the Church has continued to use this power of transferring the satisfactory value of the works of some of her members to others, to obtain the remission of temporal punishment owed to God, thus putting into practice the right conferred on the rulers of the Church by Christ Himself, who said to the apostles and their successors, the bishops: "Whatever you shall loose on earth, shall be loosed also in heaven" (Matthew, 18,18).
The enemies of the Catholic Church ridicule the idea of indulgences, and claim that they induce people to sin more freely. They charge also that indulgences have often been sold for money. To this we reply that indulgences rather induce people to give up sin, because one must be free from mortal sin before he can gain an indulgence. Moreover, although there have been abuses in the past in the matter of indulgences, that is no objection to the proper use of them. Any sacred thing can be abused by wicked persons, but it does not on that account cease to be sacred and beneficial.
Anyone who studies the Catholic doctrine of indulgences must admit that it is most reasonable. It simply means that God in His mercy Will accept the satisfactory works of some members of the Church for the benefit of others. Even in human affairs this is a common practice. If one member of a family contracts a debt, and his brothers and sisters give him money to pay it, the creditor accepts the money and regards the debt as paid. God does the same when He accepts the satisfactions of His Divine Son and of the Saints in payment for the debt of temporal punishment due to other members of the Church.
The satisfactory value of the good works performed by members of the Church who have no need of it themselves goes into the spiritual treasury of the Church, and it is then distributed by those who exercise jurisdiction in the Church, the Pope and the bishops. The Pope is not restricted as to the amount of indulgences he can grant, though even he must have a reason for granting an indulgence, since he is only the dispenser, not the owner of the Church's treasury. Nowadays a bishop can grant an indulgence of 100 days, an archbishop 200 days, a cardinal 300 days.
Plenary indulgences are numerous, and the conditions are very easy. One can even gain several plenary indulgences in a single day, by performing various works, each of which has a plenary indulgence attached to it; and even though each may demand confession and Communion, a person need receive these sacraments only once for all the indulgences he can gain in one day, Moreover, the Church allows us to gain many indulgences for the souls in purgatory. There is one indulgence especially which manifests the love of our Church for the faithful departed. It is the indulgence which can be gained on All Souls' Day, November 2nd; and it can be gained from noon of November 1st, until midnight of November 2nd. During this time a person who has been to confession and Communion can gain a plenary indulgence for the poor souls every time he visits a church or public oratory and recites six times the Our Father, the Hail Mary and the Glory be to the Father. This is a special exception to the ordinary law of the Church according to which a plenary indulgence for the same work can be gained only once a day.
When one of the conditions for gaining an indulgence is a prayer for the intention of the Pope, it suffices to say once the Our Father, the Hail Mary and the Glory be to the Father, or some other equivalent prayer. But for a plenary indulgence that can be gained repeatedly on the same day by visiting a church and praying for the Holy Father, one must recite for each indulgence six times the Our Father, Hail Mary and Glory be to the Father.