Matsya Purana — The Legend of Acchodā: Pitṛloka
तस्मात्त्वं पुत्रि तपसः प्राप्स्यसे प्रेत्य तत्फलम् अष्टाविंशे भवित्री त्वं द्वापरे मत्स्ययोनिजा //
tasmāttvaṃ putri tapasaḥ prāpsyase pretya tatphalam aṣṭāviṃśe bhavitrī tvaṃ dvāpare matsyayonijā //
Therefore, O daughter, after death you shall obtain the fruit of your austerities (tapas). In the twenty-eighth Dvāpara age, you will be born from a fish-womb, as Matsyayonijā.
This verse does not describe pralaya directly; it emphasizes karmic causality—how tapas (austerity) yields results even after death—and places the outcome within yuga chronology (Dvāpara).
It reinforces the Purāṇic ethic that disciplined tapas and dharmic conduct are meaningful across lifetimes; for householders and rulers, it supports the ideal that self-restraint and vowed practice produce enduring merit (phala), not merely immediate gains.
No Vāstu or temple-architecture rule appears in this verse; the ritual takeaway is the valuation of tapas as a legitimate sādhanā whose fruit (phala) manifests according to cosmic time (yugas).