The Mahabharata/Book 1: Adi Parva…
“ Affectionate unto one another, they all repeatedly exclaimed, 'What is our joy today, O what joy!''Then Bhima, endued with great strength and prowess, related to his brothers everything about the villainy of Duryodhana, and the lucky and unlucky incidents that had befallen him in the world of the Serpents. Thereupon Yudhishthira said, 'Do thou observe silence on this. Do not speak of this to any one. From this day, protect ye all one another with care.' Thus cautioned by the righteous Yudhishthira, they all, with Yudhishthira himself, became very vigilant from that day. ”
