Matsya Purana — Characteristics of Dvāpara and Kali Yugas
वेदश्चैकश्चतुर्धा तु व्यस्यते द्वापरादिषु ऋषिपुत्रैः पुनर्वेदा भिद्यन्ते दृष्टिविभ्रमैः //
vedaścaikaścaturdhā tu vyasyate dvāparādiṣu ṛṣiputraiḥ punarvedā bhidyante dṛṣṭivibhramaiḥ //
The Veda is one, yet in the Dvāpara age and thereafter it is arranged into four divisions. Then again, through the sons of the seers, the Vedas become further differentiated—owing to variations and confusions in human understanding.
This verse is not about Pralaya directly; it explains how sacred knowledge (the one Veda) is reorganized and later diversified across yugas due to shifts in human capacity and clarity of understanding.
It implies that dharma must be learned from the appropriate, well-preserved Vedic tradition for one’s time; a king or householder should rely on competent teachers and recognized recensions rather than personal speculation born of “dṛṣṭi-vibhrama” (confused perception).
No Vāstu or temple rule is stated explicitly; indirectly, it underscores why ritual manuals and practices can differ by śākhā (Vedic branch), since later lineages preserved and interpreted the Veda in multiple recensions.