Matsya Purana — War of Devas and Asuras; Birth of Aurva Fire; Countering Tamasī Māyā through ...
एवमुच्छिन्नमूलैश्च पुत्रैर्नो नास्ति कारणम् भवांस्तु तपसा श्रेष्ठो प्रजापातसमद्युतिः //
evamucchinnamūlaiśca putrairno nāsti kāraṇam bhavāṃstu tapasā śreṣṭho prajāpātasamadyutiḥ //
With our sons thus cutting off the very root (of the family line), there is no longer any cause for hope. But you—by your austerity—are the foremost, radiant like Prajāpati himself.
It does not describe cosmic Pralaya; it uses the metaphor of an “uprooted” line to express the dissolution of a family lineage due to the conduct of sons.
It reflects the Purāṇic concern for kula (family line) continuity and responsible progeny; it also elevates tapas as a corrective power—seeking counsel from a superior ascetic when household order collapses.
No Vāstu or temple-architecture rule is stated; the ritual takeaway is the praise of tapas (austerity) as spiritually efficacious and socially stabilizing.