There are four characters in the Srimad Bhagwad Gita - Dhrithrashtra, Sanjay, Arjuna and Sri Krishna. Together they represent the complete scale and ladder of human consciousness, the lowest being Dhrithrashtra and the highest Sri Krishna.
We all live in a kind of psychological sleep wherein we are hypnotised by every event, emotion and thought in our lives. Patanjali calls this state ‘avidya’ or the absence of light. This is our lowest state and this darkness is symbolised by Dhrithrashtra who is depicted as a blind king. His physical blindness is symbolic of his inner state of blindness, the chief cause being his attachment to his son.
Sanjay is employed by the king but never misses a chance to tell him the truth. Even on the day his ten sons have died on the battlefield, Sanjay tells him that it is his fault they are dead. The first step in any spiritual journey is to awaken the Sanjay within us. It is the awakening of our own conscience which tells us what is right and wrong, what should be done or not done. Not our normal conscience which is conditioned by education, religion and upbringing, but a deeper conscience which is universal. Every moment, Sanjay will tell us the truth about our actions so we do not continue living in self-illusion.
Sanjay is a kind of retrospect awareness. The rishi Vyasa has given him Divine Sight to tell Dhrithrashtra what is happening on the battlefield. For the first ten days of the battle, Sanjay does not use this sight. However, on the tenth day, a messenger comes to Dhrithrashtra to tell him that Bhishma has fallen in the battlefield. This shocks Dhrithrashtra and he asks Sanjay to recount everything that happened. This is why the Gita is in the past tense.
When we start observing the workings of our psyche, we can initially only study emotions in retrospect. That is, we are aware of the anger or irritation only after it has happened. This is self-study and after long practice, we come to a state in which we are able to observe while the anger is happening.
This is the awakening of the inner Arjuna who is guided by Sri Krishna, the highest state of consciousness.