What was Arjuna doing in the Mahabharata war?
Towards the end of the Drona Parva, Arjuna asks Ved Vyas, “When I was fighting the enemy forces, I envisioned a divine being who was releasing all the weapons for me. While everyone around assumed that it was me displaying valor, this great being was destroying the opponents; I was only following him. Who was this great personality?” Vyas replies that he had had a vision of Lord Shiva, the Sole Shelter and Universal Soul, Who had been continually walking in front of his chariot and battling his immoral opponents for him.
Similarly, at the conclusion of the war (Shalya Parva), as soon as Lord Krishna and Lord Hanuman exit Arjuna’s chariot, the chariot, along with the horses, instantly catches flames. Finding his chariot turned into ashes, Arjuna questions Krishna about this mysterious event. Krishna explains that his vehicle had already been destroyed by the unyielding missiles of his opponents, but it did not convert into ruins because of His presence on it. Now that He has left it, its actual state is observable.
Wait, if Krishna, Shiva, and Hanuman were battling for Arjuna, what was this jiva doing in the war? He was simply standing – standing with righteousness. This is all Krishna had expected from him while singing his renowned discourse. The rest was a play of the Lord Who always supports His righteous devotees to the ultimate extent. Because Arjuna had become a favorite of the Divine, His love resonated over him repeatedly as blessings of victory from Goddess Durga before the commencement of the battle, as the protection by Shiva and Hanuman, and as Krishna’s role as his chariot-driver, friend, and lifelong guide.