Mbh 5.157.1a

Vaisampayana said, “Dhritarashtra’s son, accompanied by all the kings, then addressed Bhishma, son of Santanu, and with joined hands said these words, ‘Without a commander, even a mighty army is routed in battle like a swarm of ants. The intelligence of two persons can never agree. Different commanders, again, are jealous of one another as regards their prowess. O thou of great wisdom, it is heard (by us) that (once on a time) the Brahmanas, raising a standard of Kusa grass, encountered in battle the Kshatriyas of the Haihaya clan endued with immeasurable energy. O grandsire, the Vaisyas and the Sudras followed the Brahmanas, so that all the three orders were on one side, while those bulls among the Kshatriyas were alone on the other. In the battles, however, that ensued, the three orders repeatedly broke, while the Kshatriyas, though alone, vanquished a large army that was opposed to them. Then those best of Brahmanas enquired of the Kshatriyas themselves (as to the cause of this). O grandsire, those that were virtuous among the Kshatriyas returned the true answer to the enquirers, saying, “In battle we obey the orders of one person endued with great intelligence, while ye are disunited from one another and act according to your individual understanding.” The Brahmanas then appointed one amongst themselves as their commander, who was brave and conversant with the ways of policy. And they then succeeded in vanquishing the Kshatriyas. Thus people always conquer their foes in battle who appoint a skilled, brave, and sinless commander, observing the good of the forces under him. As regards thee, thou art equal to Usanas himself, and always seekest my good. Incapable of being slain, thou art, again devoted to virtue. Be thou, therefore, our commander.