In the epic, Mahabharata, before the battle, Shri Krishna puts a proposal to both Duryodhana and Arjuna, who have come to seek his help. Krishna says, one can choose Krishna’s army and the other can choose Krishna himself. Duryodhana chooses the army of Krishna and Arjuna takes Krishna on his side in spite of his pledge that he would remain weaponless. Krishna becomes the chariot driver(sarathi) of Arjuna. Arjuna is the rathi or the owner of the chariot. The fighting has to be done by the rathi(Arjuna) while the sarathi(Krishna) drives the chariot. The skill and expertise with which the sarathi manoeuvres the chariot through the enemy ranks enables the rathi to exercise his prowess. A good rathi but a poor sarathi invariably spells defeat or disaster or death for the rathi.