Śvetāśvatara Upaniṣad · 1..7
यस्माद्विश्वमुत्पन्नं यस्मिन्निदं विश्वमात्मनि संप्रतिष्ठितमेकेऽस्मिन्समेते यस्मिंस्तद्ब्रह्मेति निर्दिष्टम्
yasmādviśvamutpannaṃ yasminnidaṃ viśvamātmani saṃpratiṣṭhitameke'sminsamete yasmiṃstadbrahmeti nirdiṣṭam
From whom this universe has arisen, in whom this universe exists as the Ātman, in whom all things dissolve and with whom everything unites — that is designated as Brahman.
Here we have the complete cosmic triad: sṛṣṭi (creation), sthiti (sustenance), and pralaya (dissolution). Brahman is not just the creator but the inner being (Ātman) of all that is created. The universe (viśva) is not separate from Him but exists as Him, just as the wave exists as water. In our yoga practice, when we understand that our own existence arises, is sustained, and dissolves in this ultimate Reality, the fear of death dissolves. All returns to its source, and that union is our true nature.