Matsya Purana — Catalogue of the Eighteen Puranas
निर्दग्धेषु च लोकेषु वाजिरूपेण वै मया अङ्गानि चतुरो वेदान् पुराणं न्यायविस्तरम् //
nirdagdheṣu ca lokeṣu vājirūpeṇa vai mayā aṅgāni caturo vedān purāṇaṃ nyāyavistaram //
When the worlds were burnt up, I indeed—assuming the form of a horse—recovered and safeguarded the Vedāṅgas, the four Vedas, the Purāṇa, and the extensive teaching of Nyāya (right reasoning).
It states that after cosmic devastation—when the worlds were “burnt”—the Lord preserves and restores the foundational bodies of sacred knowledge so dharma and learning can continue after Pralaya.
By highlighting the safeguarding of Veda, Purāṇa, and Nyāya, the verse implies that rulers and householders should protect learning, support teachers and recitation, and govern using dharma informed by scripture and sound reasoning.
No direct Vāstu or temple rule is stated; the ritual takeaway is that Vedic auxiliaries (Vedāṅgas) and Purāṇic tradition are divinely preserved, legitimizing post-Pralaya rites, recitation, and correct procedure grounded in śāstra.