Mbh 1.2.14a

“Listen then to (the contents of) the fifth Parva which must be known as Udyoga. While the Pandavas, desirous of victory, were residing in the place called Upaplavya, Duryodhana and Arjuna both went at the same time to Vasudeva, and said, “You should render us assistance in this war.” The high-souled Krishna, upon these words being uttered, replied, “O ye first of men, a counsellor in myself who will not fight and one Akshauhini of troops, which of these shall I give to which of you?” Blind to his own interests, the foolish Duryodhana asked for the troops; while Arjuna solicited Krishna as an unfighting counsellor. Then is described how, when the king of Madra was coming for the assistance of the Pandavas, Duryodhana, having deceived him on the way by presents and hospitality, induced him to grant a boon and then solicited his assistance in battle; how Salya, having passed his word to Duryodhana, went to the Pandavas and consoled them by reciting the history of Indra’s victory (over Vritra). Then comes the despatch by the Pandavas of their Purohita (priest) to the Kauravas. Then is described how king Dhritarashtra of great prowess, having heard the word of the purohita of the Pandavas and the story of Indra’s victory decided upon sending his purohita and ultimately despatched Sanjaya as envoy to the Pandavas from desire for peace. Here hath been described the sleeplessness of Dhritarashtra from anxiety upon hearing all about the Pandavas and their friends, Vasudeva and others. It was on this occasion that Vidura addressed to the wise king Dhritarashtra various counsels that were full of wisdom. It was here also that Sanat-sujata recited to the anxious and sorrowing monarch the excellent truths of spiritual philosophy. On the next morning Sanjaya spoke, in the court of the King, of the identity of Vasudeva and Arjuna.