सहस्रयुगपर्यन्तमहर्यद्ब्रह्मणो विदुः । रात्रिं युगसहस्रान्तां तेऽहोरात्रविदो जनाः ॥ १७ ॥
sahasra-yuga-paryantam ahar yad brahmaṇo viduḥ rātriṁ yuga-sahasrāntāṁ te ’ho-rātra-vido janāḥ
Translation
Those who know that a day of Brahma lasts a thousand yugas, and his night a thousand yugas, are the knowers of day and night.
Hindi Meaning (हिंदी अर्थ)
जो मनुष्य ब्रह्मा के एक दिन को एक हज़ार चतुर्युगी की अवधि वाला और रात्रि को भी एक हज़ार चतुर्युगी की अवधि वाली जानते हैं, वे समय के तत्त्व को जानने वाले हैं।
Commentary
The Gita's vast cosmic time scale. A day of Brahma (a kalpa) spans a thousand cycles of the four yugas — billions of human years. Against such time, even the longest human life is a moment.