Bhagavad Gita 8.17
सहस्रयुगपर्यन्तमहर्यद्ब्रह्मणो विदुः | रात्रिं युगसहस्रान्तां तेऽहोरात्रविदो जनाः ||
sahasra-yuga-paryantam ahar yad brahmaṇo viduḥ | rātriṁ yuga-sahasrāntāṁ te'ho-rātra-vido janāḥ ||
Translation
Those who know that the day of Brahmā is a thousand ages long, and the night a thousand ages long, are the knowers of day and night.
Reflection
What does your sense of time look like next to a thousand ages?
Read this verse in its chapter: Chapter Eight
He gives the timescales of Brahma's day and night. A thousand yugas long, each. The knowers of day and night know this. He is showing the seeker what counts as long even by cosmic measure. A thousand ages of unfolding, then a thousand ages of rest. The whole figure dwarfs any single human reckoning of time. He is doing this in part to humble the reader's sense of duration, and in part to set up the verses that follow, where even this enormous interval will be revealed as repeating. The reader is being recalibrated. The scales he has been using are too small for what is being described.