Matsya Purana — Śukra Warns Vṛṣaparvan: The Ripening of Adharma and Devayānī’s Demand for Śar...
यदि नात्मनि पुत्रेषु न चेत्पश्यति नप्तृषु पापमाचरितं कर्म त्रिवर्गमतिवर्तते //
yadi nātmani putreṣu na cetpaśyati naptṛṣu pāpamācaritaṃ karma trivargamativartate //
If a person does not perceive (the consequences of) sinful conduct in oneself, nor in one’s sons, nor even in one’s grandsons, that sin—once committed—nevertheless oversteps the (supposed gains of the) three aims of life (dharma, artha, and kāma).
This verse does not discuss pralaya directly; it teaches karmic causality—sin may not appear to bear fruit immediately (even across generations), yet it ultimately overrides worldly aims and brings ruin beyond dharma–artha–kāma.
It warns that judging actions only by immediate outcomes is misleading; a king or householder must avoid pāpa even if no harm is seen in oneself or one’s heirs, because sinful policy or conduct eventually destroys prosperity (artha), pleasure (kāma), and even one’s standing in dharma.
No vastu/temple rule is stated here; the takeaway is ethical—ritual merit and social order depend on avoiding pāpa, since immoral action ultimately negates the benefits sought through rites, wealth, and enjoyment.