Matsya Purana — Yayāti and His Sons: The Exchange of Youth and Old Age
*ययातिरुवाच यस्त्वं मे हृदयाज्जातो वयः स्वं न प्रयच्छसि पापान्मातुलसम्बन्धाद् दुष्प्रजा ते भविष्यति //
*yayātiruvāca yastvaṃ me hṛdayājjāto vayaḥ svaṃ na prayacchasi pāpānmātulasambandhād duṣprajā te bhaviṣyati //
Yayāti said: “You who were born from my very heart—if you do not grant me your own youth, then, because of the sinful connection with your maternal uncle’s line, you shall have wicked offspring.”
This verse does not discuss Pralaya; it belongs to the dynastic narrative where Yayāti warns/curses his son in the context of lineage, duty, and succession.
It frames filial responsibility and the ethics of succession: refusal to support one’s father (here, by granting youth) is portrayed as a grave breach with social and dynastic consequences, emphasizing duty (dharma) within the royal household.
No Vastu, temple-building, or ritual procedure is stated here; the verse is focused on genealogy, family obligation, and the karmic/dynastic outcome of conduct.