"There is no deeper pathos in the spiritual life of man [sic] than the cruelty of righteous people. If any one idea dominates the teachings of Jesus, it is his opposition to the self-righteousness of the righteous. The parable spoken unto 'certain which trusted in themselves that they are righteous, and despised others' made the most morally disciplined group of the day, his Pharisees, the object of his criticism. In fact, Jesus seems to have been in perpetual conflict with the good people of his day and ironically justified his consorting with the bad people by the remark that not those who are whole, but those who are sick, are in need of a physician...
The criticism which Jesus leveled at good people had both a religious and moral connotation. They were proud in the sight of God and they were merciless and unforgiving to their fellow-men. Their pride is the basis of their lack of mercy. The unmerciful servant, in Jesus' parable is unforgiving to his fellow-servant in spite of the mercy which he had received from his master.
Forgiving love is a possibility only for those who know that they are not good, who feel themselves in need of a divine mercy, who live in a dimension deeper and higher than that of moral idealism, feel themselves as well as their fellow men convicted of sin by a holy God and know that the difference between the good man and the bad man are insignificant in his sight. St. Paul expresses the logic of this religious feeling in the words:
"With me it is a very small thing that I should be judged of your or of man's judgment: yea, I judge not mine own self. For I know nothing by myself; yet am I not thereby justified: but he that judgeth me is the Lord."
...For this reason the the religious ideal of forgiveness is more profound and more difficult than the rational virtue of tolerance," - Reinhold Niebuhr