Do please enlighten me. My understanding is that in the sacrament of Reconciliation, what is required of the sinner is penitence, confession, and satisfaction, that last being the issue here. the CCC describes it like this:
1459 Many sins wrong our neighbor. One must do what is possible in order to repair the harm (e.g., return stolen goods, restore the reputation of someone slandered, pay compensation for injuries). Simple justice requires as much. But sin also injures and weakens the sinner himself, as well as his relationships with God and neighbor. Absolution takes away sin, but it does not remedy all the disorders sin has caused.[62] Raised up from sin, the sinner must still recover his full spiritual health by doing something more to make amends for the sin: he must “make satisfaction for” or “expiate” his sins. This satisfaction is also called “penance.”
*1460 The penance the confessor imposes must take into account the penitent’s personal situation and must seek his spiritual good. It must correspond as far as possible with the gravity and nature of the sins committed. It can consist of prayer, an offering, works of mercy, service of neighbor, voluntary self-denial, sacrifices, and above all the patient acceptance of the cross we must bear. Such penances help configure us to Christ, who alone expiated our sins once for all. They allow us to become co-heirs with the risen Christ, “provided we suffer with him.”[63]
The satisfaction that we make for our sins, however, is not so much ours as though it were not done through Jesus Christ. We who can do nothing ourselves, as if just by ourselves, can do all things with the cooperation of “him who strengthens” us. Thus man has nothing of which to boast, but all our boasting is in Christ . . . in whom we make satisfaction by bringing forth “fruits that befit repentance.” These fruits have their efficacy from him, by him they are offered to the Father, and through him they are accepted by the Father.[64] *
Additionally I understand that normally if one fails to accomplish this penance, one’s confession is invalid, and that ultimately the satisfaction at least will be made in Purgatory, as is outlined in the Catholic encyclopedia:
*There remains, however, some indebtedness to Divine justice which must be cancelled here or hereafter (see PURGATORY). In order to have it cancelled here, the penitent receives from his confessor what is usually called his “penance”, usually in the form of certain prayers which he is to say, or of certain actions which he is to perform, such as visits to a church, the Stations of the Cross, etc. Alms deeds, fasting, and prayer are the chief means of satisfaction, but other penitential works may also be enjoined. The quality and extent of the penance is determined by the confessor according to the nature of the sins revealed, the special circumstances of the penitent, his liability to relapse, and the need of eradicating evil habits. Sometimes the penance is such that it may be performed at once; in other cases it may require a more or less considerable period, as, e.g., where it is prescribed for each day during a week or a month. But even then the penitent may receive another sacrament (e.g., Holy Communion) immediately after confession, since absolution restores him to the state of grace. He is nevertheless under obligation to continue the performance of his penance until it is completed. *
The OC does not require penance as a matter of satisfaction.
