Matsya Purana — Dynastic Genealogies: Paurava–Anu Lines
विधूय मातृजं कायं ब्राह्मण्यं प्राप्तवान्विभुः ततो ऽब्रवीत्पिता तं वै पुत्रवानस्म्यहं त्वया //
vidhūya mātṛjaṃ kāyaṃ brāhmaṇyaṃ prāptavānvibhuḥ tato 'bravītpitā taṃ vai putravānasmyahaṃ tvayā //
Casting off the body derived from his mother, the mighty one attained the state of Brahminhood. Then his father said to him indeed: “Through you, I am (truly) possessed of a son.”
This verse does not describe Pralaya; it focuses on a personal transformation and the attainment of brāhmaṇya (Brahmin status), framed within a lineage narrative.
It highlights the Purāṇic emphasis on lineage, legitimacy, and dharmic identity: a father’s acknowledgement of a son signals fulfillment of household continuity (putra), which is central to gṛhastha-dharma and social stability.
No Vāstu/temple-building rule is stated here; the ritual-legal idea implied is the attainment/recognition of brāhmaṇya, a status often linked in Purāṇic contexts to eligibility for specific rites and priestly functions.