Indebted indeed.

 According to the Mahabharata and the Bhagavad Gita, Sanjaya also saw the Viśvarūpa, though in a different way from Arjuna.

The key difference is this:

Arjuna saw the Viśvarūpa because Lord Krishna directly granted him divine eyes (divya cakṣu) (Bhagavad Gita 11.8). The vision was a personal act of divine grace, intended to remove Arjuna's doubts and strengthen him for his duty.

Sanjaya saw the same events because the sage Vyasa had bestowed upon him divya dṛṣṭi (divine sight), enabling him to witness and narrate everything happening on the battlefield to Dhritarashtra from afar.

This is why Sanjaya can vividly describe the Lord's Universal Form in Chapter 11. At the beginning of the vision (Bhagavad Gita 11.9 onward), it is Sanjaya who narrates:

"Having thus spoken, the Supreme Lord Hari revealed to Arjuna His supreme, divine Universal Form."

He then goes on to describe its countless mouths, eyes, divine ornaments, celestial weapons, and immeasurable brilliance before quoting Arjuna's own words of astonishment.

Why, then, is Arjuna's experience unique?

Although both perceived the Viśvarūpa, their experiences were not identical.

Arjuna stood in the Lord's immediate presence. He was overwhelmed emotionally—filled with wonder, devotion, humility, and even trembling. The vision transformed him personally.

Sanjaya witnessed it as a divinely empowered observer. He faithfully reported what he saw to Dhritarashtra, but the revelation was not directed toward him as a personal spiritual instruction.

What about Dhritarashtra?

Ironically, Dhritarashtra heard the entire account but did not see the Universal Form. His physical blindness remained, and the Lord did not grant him divine sight. Some traditional commentators see a symbolic lesson here: merely hearing about God's greatness is invaluable, but true realization ultimately depends on divine grace and inner receptivity.

The Sri Vaishnava understanding

Sri Bhagavad Ramanujacharya accepts that Sanjaya genuinely witnessed the Viśvarūpa through Vyasa's bestowed divine vision. However, the special grace of the Lord was bestowed upon Arjuna, because the purpose of the revelation was to establish his conviction that Krishna is the Supreme Narayana and to prepare him to perform his dharma without doubt.

Thus, there were three people connected with the event:

Krishna — the revealer of the Universal Form.

Arjuna — the direct recipient of the Lord's grace and the transformative vision.

Sanjaya — the divinely empowered witness who faithfully conveyed this extraordinary revelation to Dhritarashtra and, through the Mahabharata, to all future generations.

In that sense, every reader of the Bhagavad Gita is indebted to Sanjaya, for without his divinely granted vision and narration, the world would not have received this magnificent account of the Lord's Viśvarūpa.