Manusmriti

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तद् वै युगसहस्रान्तं ब्राह्मं पुण्यमहर्विदुः । रात्रिं च तावतीमेव तेऽहोरात्रविदो जनाः ॥ ७३ ॥

sanskrit

Those (only, who) know that the holy day of Brahman, indeed, ends after (the completion of) one thousand ages (of the gods) and that his night lasts as long, (are really) men acquainted with (the length of) days and nights.

english translation

tad vai yugasahasrAntaM brAhmaM puNyamaharviduH | rAtriM ca tAvatImeva te'horAtravido janAH || 73 ||

hk transliteration by Sanscript