There [in that form] Arjuna beheld the entire universe, with its manifold divisions gathered together in one single point within the body of the God of gods.
Purport
As explained in Sh#9 Sanjaya is describing the whole event to Kuru king Dhritarashtra. Sanjaya hence says to Dhritarashtra that Arjuna hence witnesses the entire universe unfolding in the universal form of Bhagwan Shri Krishna.
