When Kunti, who had been staying at Hastinapur with Vidura, learnt from Krishna that his mission had failed and war was inevitable and soon to take place, she rushed to Karna and said, "I have come seeking forbearance and clemency."
"You embarrass me, Queen Mother. In what way could this suta ever have been offended?"
"You are not a suta (Shudra), the son of the charioteer Adiratha and Radha; you are my son born of Lord Surya. I had to part with you in extreme pain - a pain that I have lived with all my life. Karna, do not fight against your brothers, rather, join hands with Arjun, for then no power on earth could ever stand against you."
"Queen Mother, I am grateful to you for acknowledging me, even at this late hour," Karna, with more than just a tinge of scepticism in his voice, replied in a restrained and dispassionate tone. "Indeed you have given me my identity, which till now I always felt was inconsistent with my being; something that I had been searching for, yearning for, ever so long. However, as I have been denied the love and recognition that accompanies the relationship you mention, you can hardly expect me to honour that relationship."
Then, as thoughts of his rejection by Draupadi flooded him, he said a little bitterly, "In spite of all my accomplishments I am merely the suta Radheya, son of a charioteer, someone of no consequence, dust that may be brushed aside. Though it is the unstinted love of my mother, Radha, that sustains me, whatever I am today, whatever I have today, is on account of Duryodhana. I am and shall remain ever indebted to him. I shall not abandon him."
Karna continued, "You did not fulfil the obligations of a mother but your son shall fulfil his. You have come seeking something of me and it shall not be said that Radheya let one return empty-handed. Ask what you want."
"O greatest of the danaveera, what can a mother ask save the lives of her sons?"
Mastering his emotions, Karna, supressing the sigh that almost escaped him, replied dispassionately, "I grant you this boon: barring Arjuna I shall not kill any of your other sons and that either Arjuna or I shall get killed. Either way, five of your sons will survive and you will continue to be known as 'the mother of five sons'."
Kunti, though distressed, could do nothing more. Karna, seeking her leave, said, "Please ... a request, let not my brothers know of this relationship. Righteous as they are, they will not lift their arms against me ... which must not be." Then, as he bent down to touch her feet, he added, almost inaudibly, but with great feeling, "Mother." Kunti, overwhelmed, turned quickly and walked away as swiftly as she could.
Later that evening, Krishna, too, visited Karna and tried to reason with him. "As already revealed to you by your mother, you are the eldest of the Pandavas and as the eldest, And since Arjuna was asked by Kunti to share Draupadi with all his brothers, she is your wife too. Should you change sides, you will be the king of Indra-prastha and Draupadi will be your queen and the five Pandavas will serve you and Kunti will bless you." said Krishna
Karna looked at Krishna and said, "You flatter me with your bribes and your words. But I stand true to my word. Righteous or not, I will stand by Duryodhana and die for him, even if it means fighting my own brothers."
Karna looked at Krishna and said, "And there is another reason."
"And that is?" enquired Krishna.
"Draupadi." Then, as the full scene where the atrocity was committed upon Draupadi flashed in his mind, he continued "I was not merely instrumental in her humiliation and kept watching as she was being humiliated, I, in fact, humiliated her. As long as I live I can never forgive myself. I cannot understand what came over me. How could I have degraded myself so? It's absolutely unforgiveable. I can never face her, ever."
"That's the effect of the company you keep. Some of it will certainly rub off on you. However, remorse and repentance opens the doors of forgiveness," said Krishna and left.