Matsya Purana — Yadu Lineage
गतेषु सुरसंघेषु शक्रं विष्णुरभाषत मां त्वं प्रविश भद्रं ते नयिष्ये त्वां सुरोत्तम //
gateṣu surasaṃgheṣu śakraṃ viṣṇurabhāṣata māṃ tvaṃ praviśa bhadraṃ te nayiṣye tvāṃ surottama //
When the hosts of gods had departed, Viṣṇu spoke to Śakra (Indra): “Enter into me—may it be well with you. O best of the gods, I shall carry you through and lead you safely onward.”
This verse is not about pralaya directly; it highlights Viṣṇu’s role as cosmic protector, a theme that also underlies pralaya narratives where beings seek refuge in the preserving deity.
Indra is portrayed as the archetypal ruler seeking guidance; the ethical parallel is that a king (or householder) should seek wise counsel, take refuge in dharma, and accept protection/leadership from a higher principle rather than acting from fear or isolation.
No explicit Vāstu or ritual procedure is stated; the key takeaway is the devotional-ritual principle of śaraṇāgati (seeking refuge), often expressed in pūjā through invoking Viṣṇu as protector before undertaking major rites.