Standing between the two forces, the good and the bad, arrayed for a battle to death, Arjuna (the jiva) surrenders completely to the Lord (the subtler discriminative intellect), his charioteer, who holds the five horses (the five senses) yoked to his chariot (body) under perfect control.
When the stunned and confused ego – Arjuna -, totally surrenders to Krishna, the Lord, with a smile, reassures the Jiva of its final victory and declares the entire message of spiritual redemption, the Gita.
When the ego (Arjuna) on its dejection sits back in the body (chariot), throwing down all instruments of egocentric activities (Gandiva), and when the sense organs (the white horses) are held back, well under control, by the pulled-reins (the mind), then the charioteer (the pure intellect) shall lend the ego a divine strength and guide it to the ultimate victory over the forces of adharma (Kauravas) with the help of the dynamism of dharma (Pandavas), even though the former may seem much stronger in force than the simple-looking dynamism in the latter.