Praśna Upaniṣad · 1..7
स एष वैश्वानरो विश्वरूपः प्राणोऽग्निरुदयते तदेतदृचाऽभ्युक्तम्
sa eṣa vaiśvānaro viśvarūpaḥ prāṇo'gnirudayate tadetadṛcā'bhyuktam
He, that Vaiśvānara of universal forms, Prāṇa, the fire, rises. Of this it has been spoken in a Ṛgveda verse.
Here the sun is identified with Vaiśvānara — the cosmic fire present in all beings (viśva = all, ānara = fire). This is a profound concept: the same vital principle that animates the entire universe also resides within our interior.
The triple identification — sun, Prāṇa, fire — is significant. Fire (agni) in the human body is digestion, metabolic transformation. Cosmic fire is the sun. And spiritual fire is consciousness itself. The three are one.
Viśvarūpa — “of universal forms” — indicates that Prāṇa does not have a single manifestation, but innumerable ones. It is the unifying principle expressed in all the diversity of the cosmos.
The reference to the Ṛgveda connects this teaching with the oldest tradition of śruti. The teacher Pippalāda does not invent, but transmits timeless wisdom.
For the yogī, Vaiśvānara is also the energy center of the navel (maṇipūra cakra), where the digestive and vital fire is said to reside. Harmonizing this center is fundamental for health and spiritual evolution.