Verse
सहस्रयुगपर्यन्तम् अहर्यद् ब्रह्मणो विदुः ।रात्रिं युगसहस्रान्तां तेऽहोरात्रविदो जनाः ॥
sahasrayugaparyantam aharyad brahmaṇo viduḥrātriṃ yugasahasrāntāṃ te’horātravido janāḥ
Those who know the day of Brahma, a thousand ages (Yugas) in duration, and the night, a thousand ages in ending, they are the knowers of day and night.
Gītā 8·17There is an eternal cycle of alternating periods of cosmic manifestation and non-manifestation, each period called respectively a day and a night of the creator Brahma, each of equal length in Time, the long aeon of his working which endures for a thousand ages, the long aeon of his sleep of another thousand silent ages.
