Srimad-Bhagavatam: Canto 2 - Chapter 1 - Verse 13
Sanskrit:
कालस्यानुगतिर्या तु लक्ष्यतेऽण्वी बृहत्यपि ।यावत्य: कर्मगतयो यादृशीर्द्विजसत्तम ॥ १३ ॥
ITRANS:
kālasyānugatir yā tulakṣyate ’ṇvī bṛhaty apiyāvatyaḥ karma-gatayoyādṛśīr dvija-sattama
Translation:
O purest of the brāhmaṇas, please also explain the cause of the different durations of time, both short and long, as well as the beginning of time, following the course of action.