Srimad-Bhagavatam: Canto 3 - Chapter 1 - Verse 3
Sanskrit:
एवं कालोऽप्यनुमित: सौक्ष्म्ये स्थौल्ये च सत्तम ।संस्थानभुक्त्या भगवानव्यक्तो व्यक्तभुग्विभु: ॥ ३ ॥
ITRANS:
evaṁ kālo ’py anumitaḥsaukṣmye sthaulye ca sattamasaṁsthāna-bhuktyā bhagavānavyakto vyakta-bhug vibhuḥ
Translation:
One can estimate time by measuring the movement of the atomic combination of bodies. Time is the potency of the almighty Personality of Godhead, Hari, who controls all physical movement although He is not visible in the physical world.