Matsya Purana — The Greatness of Prayaga: Manasa Tirtha
ततः स्वर्गात्परिभ्रष्टो जम्बूद्वीपपतिर्भवेत् स भुक्त्वा विपुलान्भोगांस् तत्तीर्थं स्मरते पुनः //
tataḥ svargātparibhraṣṭo jambūdvīpapatirbhavet sa bhuktvā vipulānbhogāṃs tattīrthaṃ smarate punaḥ //
Then, when he falls away from heaven, he is born as a sovereign lord of Jambūdvīpa. Having enjoyed abundant pleasures, he remembers that sacred ford (tīrtha) again.
It does not discuss pralaya directly; it teaches karmic return—after heavenly merit is spent, one falls from svarga and takes rebirth, here as a powerful ruler.
It frames kingship as a fruit of prior dharma (especially tīrtha-related merit) and implies that prosperity should be accompanied by continued remembrance of sacred duty rather than mere enjoyment.
The ritual emphasis is on tīrtha-smaraṇa—remembering the sacred place—as a continuing spiritual practice; no specific Vāstu or temple-building rule is stated in this verse.