Mbh 5.62.1a

Vaisampayana said, “Without much minding Dhritarashtra, the son of Vichitravirya who was about to ask of Partha, Karna said unto Dhritarashtra’s son these words, cheering up the spirit of the assembled Kurus, ‘Coming to know of the false pretence under which I obtained the Brahma weapon of old from Rama, the latter told me,--“When thy hour will come thy memory will fail thee in respect of this weapon.” Even for so great an offence I was cursed so lightly by that great Rishi, my preceptor. That great Rishi of fierce energy is capable of consuming even the entire Earth with her seas. By attention and personal bravery, I appeased his heart. I have that weapon with me still, and my period is not yet run. I am, therefore, fully competent (to win victory). Let the responsibility be mine. Having obtained the favour of that Rishi, I will slay within the twinkling of an eye the Panchalas, the Karushas, the Matsyas, and the sons of Pritha with their sons and grandsons, and bestow on thee numerous regions won by my weapons. Let the Grandsire and Drona and all the kings stay with thee. I will slay the sons of Pritha, marching forth with the chief warriors of my army. Let that task be mine.’ Unto him speaking thus, Bhishma said, ‘What sayest thou, O Karna? Thy intellect is clouded at the approach of thy hour. Knowest thou not, O Karna, that when the chief is slain, the sons of Dhritarashtra will all be slain? Having heard of the feat achieved by Dhananjaya, with Krishna only as his ally, at the burning of the Khandava forest, it behoveth thee with thy friends and relatives to restrain thy mind. The shaft that the illustrious and adorable chief of the celestials, the great Indra, gave thee, thou wilt see, will be broken and reduced to ashes when struck by Kesava with his discus.