Arjuna is building a portrait of the divine, and each stroke adds a new dimension. Original God. Ancient Being. The supreme treasure of the universe. The knower. The thing to be known. The supreme abode. The one by whom everything — everything — is pervaded.
The phrase 'param nidhanam' — supreme treasure, ultimate resting place — is worth pausing on. A treasure is something precious that you seek. A resting place is where you arrive at the end of a long journey. Krishna is both: the goal of seeking and the end of seeking. The destination and the peace that comes with arriving.
And then the final declaration: 'By You, all this universe is pervaded.' Not created and set aside. Not built and then abandoned. Pervaded — present in every atom, every moment, every being. Like salt dissolved in water, present everywhere but visible nowhere. Arjuna addresses Krishna as 'Anantarupa' — one of infinite forms — because no single form, no single name, no single description can ever contain what he is seeing.