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

Sanskrit:

प्रकृतिर्यस्योपादानमाधारः पुरुषः परः ।सतोऽभिव्यञ्जकः कालो ब्रह्म तत्‍त्रितयं त्वहम् ॥ १९ ॥

ITRANS:

prakṛtir yasyopādānamādhāraḥ puruṣaḥ paraḥsato ’bhivyañjakaḥ kālobrahma tat tritayaṁ tv aham

Translation:

The material universe may be considered real, having nature as its original ingredient and final state. Lord Mahā-Viṣṇu is the resting place of nature, which becomes manifest by the power of time. Thus nature, the almighty Viṣṇu and time are not different from Me, the Supreme Absolute Truth.

Purport:

Material nature is the energy of the Lord, Mahā-Viṣṇu is His plenary portion, and time represents the Lord’s activity. In this way, time and nature are always subservient to the Supreme Personality of Godhead, who creates, maintains and annihilates all that exists through the agency of His potencies and plenary portions. In other words, Lord Kṛṣṇa is the Absolute Truth because He contains all existence within Himself.