Bhagavad-gītā As It Is · Text 8.17
Mortality, cosmic cycles and eternal destination
सहस्रयुगपर्यन्तमहर्यद्ब्रह्मणो विदु: ।
रात्रिं युगसहस्रान्तां तेऽहोरात्रविदो जना: ॥ १७ ॥
sahasra-yuga-paryantam
ahar yad brahmaṇo viduḥ
rātriṁ yuga-sahasrāntāṁ
te ’ho-rātra-vido janāḥ
By human calculation, a thousand ages taken together form the duration of Brahmā’s one day. And such also is the duration of his night.
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