Mbh 12.54.5a

"'Vasudeva said, "Know, O thou of Kuru's race, that I am the root of fame and of everything that leads to good. All things, good or bad, proceed from me. Who on earth will wonder if the moon be said to be of cool rays? Similarly, who will wonder if I were described as one possessed of the full measure of fame?[159] I have, however, resolved to enhance thy fame, O thou of great splendour! It is for this, O Bhishma, that I have just inspired thee with great intelligence. As long, O lord of earth, as the earth will last, so long will thy fame travel with undiminished lustre through all the worlds. Whatever, O Bhishma, thou wilt say unto the inquiring son of Pandu, will be regarded on earth to be as authoritative as the declarations of that Vedas. That person who will conduct himself here according to the authority of thy declarations, will obtain hereafter the reward of every meritorious act. For this reason, O Bhishma, I have imparted to thee celestial understanding so that thy fame may be enhanced on earth. As long as a man's fame lasts in the world, so long are his achievements said to live. The unslain remnant of the (assembled) kings are sitting around thee, desirous of listening to thy discourses on morality and duty. Do thou speak unto them, O Bharata! Thou art old in years and thy behaviour is consistent with the ordinance of the Srutis. Thou art well conversant with the duties of kings and with every other science of duty. No one has ever noticed the slightest transgression in thee from thy very birth. All the kings know thee to be conversant with all the sciences of morality and duty. Like a sire unto his sons do thou, therefore, O king, discourse unto them of high morality. Thou hast always worshipped the Rishis and the gods. It is obligatory on thee to discourse on these subjects in detail unto persons desirous of listening to discourse on morality and duty. A learned person, especially when solicited by the righteous, should discourse on the same.