Matsya Purana — Agastya’s Origin
न धर्माधर्मसंयोगं प्राप्नुवन्त्यमराः क्वचित् भवतोस्तु विशेषेण माहात्म्यं चाधितिष्ठतोः //
na dharmādharmasaṃyogaṃ prāpnuvantyamarāḥ kvacit bhavatostu viśeṣeṇa māhātmyaṃ cādhitiṣṭhatoḥ //
The immortals never, at any time, come into contact with a mixture of dharma and adharma. But you two—most especially—stand established in true greatness and sacred eminence (māhātmya).
This verse does not describe pralaya directly; it emphasizes moral-metaphysical purity—devas are not said to be entangled in mixed dharma and adharma, highlighting a realm of order rather than dissolution.
It implies that exemplary persons should avoid compromising mixtures of right and wrong; for kings and householders, it supports the Matsya Purana’s ethical ideal of acting with clear dharmic intent rather than blending virtue with self-serving adharma.
No direct Vastu or temple-ritual rule is stated; indirectly, it supports the ritual principle of purity (śuddhi)—that sacred acts and statuses should not be performed with morally mixed motivations.