Matsya Purana — The Slaying of Jambha and the Rise of Tāraka: Divine Battle Formations
दैत्येन्द्राः स्वैर्वधोपायैः शक्या हन्तुं हि नान्यतः दुर्जयस्तारको दैत्यो मुक्त्वा सप्तदिनं शिशुम् //
daityendrāḥ svairvadhopāyaiḥ śakyā hantuṃ hi nānyataḥ durjayastārako daityo muktvā saptadinaṃ śiśum //
The lords of the Dānavas can indeed be slain only by the very means ordained for their death—by no other way. And the hard-to-conquer demon Tāraka, too, could be overcome only after the child had been left unharmed for seven days.
It does not speak directly about Pralaya; it emphasizes cosmic law (niyati) that certain beings can be overcome only through specifically ordained conditions and means.
It implies a dharmic principle relevant to governance: success against powerful adversaries depends on right method and timing, not mere force—one must act according to appropriate upāya (strategy aligned with law and circumstance).
No Vāstu or temple-ritual rule is stated in this verse; the focus is on mythic conditions for slaying a daitya (Tāraka) and the seven-day condition involving the child.