Matsya Purana — Catalogue of the Eighteen Puranas
यत्राधिकृत्य शकुनीन् धर्माधर्मविचारणा व्याख्याता वै मुनिप्रश्ने मुनिभिर्धर्मचारिभिः //
yatrādhikṛtya śakunīn dharmādharmavicāraṇā vyākhyātā vai munipraśne munibhirdharmacāribhiḥ //
There, with reference to omens (śakuna), the inquiry into what is dharma and what is adharma was indeed explained—when the sages asked—by sages devoted to dharma.
This verse does not describe Pralaya; it highlights a didactic setting where sages explain how to discern dharma and adharma, using omens as a discussion framework.
It supports dharma-based governance and household conduct by implying that decisions—especially in uncertain situations—should be guided by learned, dharma-observant authorities and careful ethical discernment (not impulse).
No direct Vāstu or temple-architecture rule is stated; the ritual takeaway is methodological: auspicious/inauspicious signs (śakuna/nimitta) are treated as a legitimate topic for dharmic interpretation by qualified sages.