When Krishna asked Arjuna why he chose Him when He was not for taking up arms, Arjuna said, "O Lord! You have the power to destroy all the forces by a mere sight. Why then should I prefer that worthless army? I have for a long time been cherishing a desire in my heart that you should act as my charioteer. Kindly fulfil my desire in this war." The Lord, who is ever the most devoted lover of His devotees, accepted his request with pleasure; and thus Krishna became the charioteer of Arjuna in the battle of the Mahabharata.After the return of Duryodhana and Arjuna from Dwaraka, Lord Krishna Himself went once to Hastinapura as the emissary of the Pandavas and tried to prevent the war. But then, under the guidance of Sakuni, the egoistic Duryodhana refused to agree to the peace mission and tried to imprison Lord Krishna, at which Krishna showed His Supreme Form (Viswarupa). Even the blind Dhritarashtra saw it by the Lord's Grace. King Dhritarashtra, due to his attachment to his sons, failed to control them, and the Kaurava chief, Duryodhana, with vain hope, decided to meet the powerful Pandavas in war.When both sides were prepared to commence the battle, the sage Veda Vyasa approached blind Dhritarashtra and said, "If you wish to see this terrible carnage with your own eyes I can give you the gift of vision." The Kaurava king replied, "O Chief of the Brahmarishis! I have no desire to see with my own eyes this slaughter of my family, but I should like to hear all the details of the battle."Then the sage conferred the gift of divine vision on Sanjaya, the trusty counsellor of the king, and told the king, "Sanjaya will describe to you all the incidents of the war. Whatever happens in the course of the war, he will directly see, hear or otherwise come to know. Whether an incident takes place before his eyes or behind his back, during the day or during the night, privately or in public, and whether it is reduced to actual action or appears only in thought, it will not remain hidden from his view. He will come to know everything, exactly as it happens. No weapon will touch his body nor will he feel tired."After the ten days of continued war between the Pandavas and the Kauravas, when the great warrior Bhishma was thrown down from his chariot by Arjuna, Sanjaya announces the news to Dhritarashtra. In agony the king asks Sanjaya to narrate the full details of the previous ten days war, from the very beginning, in all detail as it happened. Here commences the Bhagavad Gita.