Orthodox Chinese Buddhism
Do Buddhists Believe That Repentance Is Effective?
Yes, Buddhists definitely believe in the effectiveness of repentance. While completed acts of killing, stealing, sexual misconduct, and major deception (falsely claiming that one is a noble one) will definitely bring about retribution for the perpetrator, other misdeeds, such as attempted offences, unintentional breaking of the precepts, and failures to follow the rules of dignified conduct [for monastics] can all be repented with all retribution dissolved in accordance with the methods prescribed by the Buddha.
The function of repentance is to initiate a relentless process of self-reflection and self-discipline, to develop vigilance based on self-awareness, and to purify one's mind with self-respect, so as to prevent the occurrence of the same mistake. As long as one has the determination to start afresh, and realizes that the past is gone and there is no point in dwelling on it, one's mind will be relieved from the feeling of guilt and will regain serenity. This is the function of repentance. The wrongdoing has to be honestly revealed (to the community, or to several persons, or to one person, or to one's own conscience, in accordance with the category and degree of wrongdoing, followed by genuine regret and a resolution not to repeat it). Otherwise the shadow of the misdeed will be hidden permanently in the mind, and will develop into karmic seeds that invite retribution later. Repentance immediately dissolves from one's consciousness the seeds produced by the misdeed.
However, the purpose of repentance is to cleanse one's mind to prevent reoccurrence of wrongdoing. If one repeatedly misbehaves, repents, and then misbehaves again, then the efficacy of repentance will be lost. Moreover, the repentance of Buddhists is quite different from that of Christians, who pray to God for absolution. Buddhists do not believe any god has the power to absolve sin. To Buddhists, the real meaning of repentance is to cleanse the contaminated mind in order to restore its purity.
Orthodox Chinese Buddhism, Do Buddhists Believe That Repentance Is Effective?, p.45-46