Today, in the Gospel, Peter consults Jesus about a very specific topic that remains in the hearts of many people: he asks about the limit of forgiveness. The answer is that there is no such limit: "I say to you, not seven times but seventy-seven times” (Mt 18:22). To explain this reality, Jesus uses a parable. The king's question centers the theme of the parable: “Should you not have had pity on your fellow servant, as I had pity on you?” (Mt 18:33).

Forgiveness is a gift, a grace that comes from the love and mercy of God. For Jesus, forgiveness has no limits, as long as the repentance is sincere and truthful. But it demands opening the heart to conversion, that is, acting towards others according to God's criteria.

Grave sin separates us from God (cf. Catechism of the Catholic Church n. 1470). The ordinary way to receive God's forgiveness for serious sin is the sacrament of Penance, and the act of the penitent that crowns it is satisfaction. The specific works that manifest this satisfaction are a sign of the personal commitment—that the Christian has made before God—to begin a new existence, repairing the harm done to one's neighbor as much as possible.

There can be no forgiveness of sin without some form of satisfaction, the purpose of which is: 1. To avoid slipping into more severe sins; 2. To reject sin (since doing penance acts as a brake with the past, and makes the penitent more cautious and vigilant moving forward); 3. To replace bad habits contracted from sinful living with virtuous actions; 4. To help the penitent become more conformed to Christ.

As Saint Thomas Aquinas explained: “Man becomes God's debtor in two ways; first, by reason of favors received, secondly, by reason of sin committed: and just as thanksgiving or worship or the like regard the debt for favors received, so satisfaction regards the debt for sin committed.” The man in the parable was not willing to do the latter, so he became incapable of receiving forgiveness.