Matsya Purana — Solar–Lunar Motions
नवयोजनसाहस्रो विस्तारो मण्डलस्य तु विस्तारात्त्रिगुणश्चापि परिणाहो ऽत्र मण्डले //
navayojanasāhasro vistāro maṇḍalasya tu vistārāttriguṇaścāpi pariṇāho 'tra maṇḍale //
The breadth of the maṇḍala is said to be nine thousand yojanas; and in this maṇḍala, its circumference is three times its breadth.
This verse is not about Pralaya; it belongs to the Matsya Purana’s Vāstuvidyā material and states a proportional rule for the maṇḍala’s extent and circumference.
It supports dharmic governance and household/royal duties indirectly by prescribing standardized measurements for planning sacred or civic spaces—an expected responsibility in orderly settlement and temple construction.
It gives a technical proportion: the maṇḍala’s perimeter (pariṇāha) is three times its breadth (vistāra), a rule used in sacred geometry and vāstu-based layout calculations.