The Prashna Upanishad with Shankara’s Commentary
इन्द्रस्त्वं प्राण तेजसा रुद्रोऽसि परिरक्शिता ।
त्वमन्तरिक्शे चरसि सूर्यस्त्वं ज्योतिषां पतिः ॥ ९ ॥
indrastvaṃ prāṇa tejasā rudro'si parirakśitā |
tvamantarikśe carasi sūryastvaṃ jyotiṣāṃ patiḥ || 9 ||
9. Oh Prâna, you are Indra, you are Rudra by valour; you are the protector; you move in the sky and you are the Sun, the lord of all luminaries.
Com.— Again, Oh Prâna, you are Indra, i.e., Paramêsvara (Lord of all). By valour, you are Rudra, destroyer of the world and you are the protector of the world, while it endures, by your mild aspect; you always move in the inter-space. By rising and setting, you are, indeed, the sun, the lord of all orbs of light.