Srimad-Bhagavatam: Canto 11 - Chapter 1 - Verse 19

Sanskrit:

यथा हिरण्यं स्वकृतं पुरस्तात्पश्चाच्च सर्वस्य हिरण्मयस्य ।तदेव मध्ये व्यवहार्यमाणंनानापदेशैरहमस्य तद्वत् ॥ १९ ॥

ITRANS:

yathā hiraṇyaṁ sv-akṛtaṁ purastātpaścāc ca sarvasya hiraṇ-mayasyatad eva madhye vyavahāryamāṇaṁnānāpadeśair aham asya tadvat

Translation:

Gold alone is present before its manufacture into gold products, the gold alone remains after the products’ destruction, and the gold alone is the essential reality while it is being utilized under various designations. Similarly, I alone exist before the creation of this universe, after its destruction and during its maintenance.

Purport:

Gold is manufactured into many types of jewelry, as well as into coins and other luxurious products. But at each stage — before manufacture, during manufacture, during utilization and afterward — the essential reality is gold. In the same way, the Supreme Personality of Godhead is the essential reality — both the dynamic and the ingredient cause of everything. All throughout the material creation, the Lord is simply setting into motion His own potency, which is not different from Him.