Arjuna asked: O supreme Lord, what is Brahman (supreme Reality)? What is spiritual presence? What is cosmic activity? What is said to be the material manifestation? What is described as the divine manifestation?
Arjuna assimilates Krishna’s exposure, and yearns to know further. Where was his scorching grief, and where now is his undaunted quest for spiritual wisdom!
Responding to what Krishna hints at, he seeks clarification on the concepts introduced in the last chapter. Perhaps Arjuna did not know how great the domain is. Now that he had an opportunity to know about it well, he felt he should not be reluctant or shy in seeking to know more.
How even the most aggrieved mind could soar to such heights of wisdom! A great revelation for all times!
This is how direct exposure from a Knower works on a humble mind. This is the benefit of satsanga.