Matsya Purana — The Greatness of Prayāga
सर्वाणि तानि संत्यज्य कथमेकं प्रशंससि अप्रमाणं तु तत्रोक्तम् अश्रद्धेयमनुत्तमम् //
sarvāṇi tāni saṃtyajya kathamekaṃ praśaṃsasi apramāṇaṃ tu tatroktam aśraddheyamanuttamam //
After setting aside all those, how can you praise just one? For there it has been stated to be without valid proof—unreliable and yet claimed as ‘supreme’.
This verse does not describe pralaya directly; it frames a methodological concern—how to trust a ‘supreme’ claim if it is labeled apramāṇa (unsupported) and aśraddheya (unreliable).
It supports dharmic decision-making: a king or householder should not adopt a single policy or teaching merely by praise, but should examine pramāṇa (credible authority) and cultivate informed śraddhā (well-grounded trust).
No direct Vāstu or ritual procedure is stated; the takeaway is indirect—ritual or temple-building prescriptions should be followed only when grounded in accepted pramāṇa, not when deemed aśraddheya.