Matsya Purana — War of Devas and Dānavas: Yama and Kubera Defeated; Kālanemi’s Māyā and the A...
तस्थावचेष्टो दनुजो यथा धीरो धराधरः स मुहूर्तं समाश्वस्तो दानवेन्द्रो ऽतिदुर्जयः //
tasthāvaceṣṭo danujo yathā dhīro dharādharaḥ sa muhūrtaṃ samāśvasto dānavendro 'tidurjayaḥ //
The Danu-born demon stood motionless, like a steadfast mountain; after a brief moment, that hard-to-conquer lord of the Dānavas regained his composure.
This verse does not address Pralaya; it is a battlefield description emphasizing steadiness and recovery of a Dānava leader.
Indirectly, it highlights an ideal of dhairya (steadfast composure): even amid danger one should regain self-control quickly—an ethic valued for rulers and disciplined householders alike.
No Vāstu or ritual procedure is stated; the only technical image is metaphorical—'like a mountain'—used to convey immovability and resolve.