Mahabharata Udyoga Parva Chapter 155:2

Mahabharata Udyoga Parva (Bhagwat Yana Parva) Chapter 155:2 Vaisampayana continued, "Hearing these words uttered by Vasudeva, all the kings (there present), O Bharata, without saying anything, looked at Yudhishthira's face. And Yudhishthira, understanding the intention of those monarchs, said, with Bhima and Arjuna and the twins, 'Draw up the troops in battle array.' And the word of command having been passed, a great uproar rose amongst the Pandava army and all the soldiers were filled with joy. King Yudhishthira the Just, however, beholding the (impending) slaughter of those that deserved not to be slain, began to sigh deeply, and addressing Bhimasena and Vijaya, said, 'That for the sake of which I accepted an exile into the woods and for which I suffered so much misery, that great calamity overtaketh us of a set purpose. That for which we strove so much leaveth us as if on account of our very striving. On the other hand, a great distress overtaketh us, although we did nothing to invite it. How shall we fight with those reverend superiors (of ours) whom we on no account can slay? What kind of victory shall we achieve by slaying our preceptors of venerable age? Hearing these words of king Yudhishthira the Just, Savyasachin repeated to his elder brother all those words that Vasudeva had said. And addressing Yudhishthira, Arjuna continued, 'Thou hast, O king, certainly understood all the words spoken by Kunti and Vidura, that were repeated to thee by Devaki's son. I know it for certain that neither Vidura nor Kunti would say anything that is sinful. Besides this, O son of Kunti, we cannot withdraw without engaging in battle. Hearing this speech of Savyasachin, Vasudeva also said unto Partha, 'It is even so (as thou hast said).' The sons of Pandu then, O great king, made up their minds for war, and passed that night with their soldiers in great happiness.