Matsya Purana — Narasimha’s Victory over Hiraṇyakaśipu and the Catalogue of Apocalyptic Omens
दीप्तान्यन्तर्जलस्थानि पृथिवीधरणानि च तदा क्रुद्धेन महता कम्पितानि समन्ततः //
dīptānyantarjalasthāni pṛthivīdharaṇāni ca tadā kruddhena mahatā kampitāni samantataḥ //
Then, by that mighty wrath, the earth-supporting mountains—those situated within the waters—were set ablaze and shaken on every side.
It portrays pralaya-like upheaval: even the earth’s stabilizers (mountains, including those in the ocean) are aflame and quaking, signaling cosmic destabilization and approaching dissolution.
Indirectly, it frames impermanence and the need for dharmic preparedness—rulers and householders should uphold order, perform rites, and protect society, knowing that even the natural world can be overturned in times of cosmic crisis.
No direct Vastu rule is stated, but the imagery underscores why Matsya Purana ritual traditions emphasize appeasement and stability (śānti rites) when signs like tremors, fires, or abnormal natural events threaten the land.