“It is not unreasonable to want repentance from a wrongdoer before forgiving that wrongdoer, since, in the absence of repentance, hasty forgiveness may harm both the forgiver and the wrongdoer. The forgiver may be harmed by a failure to show self-respect. The wrongdoer may be harmed by being deprived of an important incentive - the desire to be forgiven - that could move him toward repentance and moral rebirth.”