The Fathers:

St. Cyprian of Carthage, The Lapsed (251 A.D.): "The Lord alone is able to have mercy. He alone, who bore our sins, who grieved for us, and whom God delivered up for our sins, is able to grant pardon for the sins which have been committed against Him...Certainly we believe that the merits of the martyrs and the works of the just will be of great availwith the Judge - but that will be when the day of judgment comes, when, after the end of this age and of the world, His people shall stand beforethe tribunal of Christ."

St. Ambrose of Milan, Penance (C. 387-390 A.D.): "For he is purged as if by certain works of the whole people, and is washed in the tears of the multitude; by the prayers and tears of the multitude he is redeemed from sin, and is cleansed in the inner man. For Christ granted to His Church that one should be redeemed through all, just as His Church was found worthy of the coming of the Lord Jesus so that all might be redeemed through one."

St. Augustine of Hippo, Homilies on the Gospel of John (416 et417 A. D.): " is obliged to suffer, even when his sins are forgiven,...for the penalty is of longer duration than the guilt, lest the guilt should be accounted small, were the penalty also to end with it. It is for this reason...that man is held in this life to the penalty, even when he is no longer held to the guilt unto eternal damnation."

St. Caesarius of Arles (+542 A.D.), Sermon 261: "Considering the number of sins, he sees that he is incapable of himself alone to make satisfaction for such grave evils; and so he is anxious to seek out the assistance of the whole people."

Catechism of the Council of Trent (1566):

No reference was made to Indulgences in the Catechism of the Council of Trent. The question of Indulgences was dealt with by the Council itself in its Decree Concerning Indulgences, Session XXV, December 3 and 4, 1563:

"Whereas the power of conferring indulgences was granted by Christ to the Church; and she has, even in the most ancient times, used the said power, delivered unto her of God; the sacred, holy synod teaches and enjoins that the use of indulgences for the Christian people, most salutary and approved of by the authority of sacred councils, is to be retained in the Church; and it contemns with anathema those who either assert that they are useless, or who deny that there is in the Church the power of granting them."