Mbh 12.56.2

"'Yudhishthira said, "Persons conversant with duty and morality say that kingly duties constitute the highest science of duty. I also think that the burden of those duties is exceedingly onerous. Do thou, therefore, O king, discourse on those duties. O grandsire, do thou speak in detail on the duties of kings. The science of kingly duties is the refuge of the whole world of life. O thou of Kuru's race, Morality, Profit, and Pleasure are dependent on kingly duties. It is also clear that the practices that lead to emancipation are equally dependent on them. As the reins are in respect of the steed or the iron hook in respect of the elephant, even so the science of kingly duties constitutes the reins for checking the world. If one becomes stupefied in respect of the duties observed by royal sages, disorder would set in on the earth and everything will become confused. As the Sun, rising, dispels inauspicious darkness, so this science destroys every kind of evil consequence in respect of the world. Therefore, O grandsire, do thou, for my sake, discourse on kingly duties in the first instance, for thou, O chief of the Bharatas, art the foremost of all persons conversant with duties. O scorcher of foes, Vasudeva regards thee as the first of all intelligent persons. Therefore, all of us expect the highest knowledge from thee."