Matsya Purana — The Nakṣatra-Puruṣa Vrata: Worship of Viṣṇu’s Cosmic Body through the Lunar M...
कटिं नमः शार्ङ्गधराय विष्णोः सम्पूजयेन्नारद कृत्तिकासु तथार्चयेद्भाद्रपदाद्वये च पार्श्वे नमः केशिनिषूदनाय //
kaṭiṃ namaḥ śārṅgadharāya viṣṇoḥ sampūjayennārada kṛttikāsu tathārcayedbhādrapadādvaye ca pārśve namaḥ keśiniṣūdanāya //
With the mantra, “Homage at the waist to Viṣṇu, the bearer of the Śārṅga bow,” one should duly worship that limb. O Nārada, one should likewise perform worship in the Kṛttikā asterism, and also offer worship in the two Bhādrapadas; and at the sides (flanks) one should say, “Homage to Keśiniṣūdana (the slayer of Keśin).”
This verse does not discuss pralaya; it focuses on ritual procedure—limb-wise salutations and auspicious timing (nakṣatras) for worship of Viṣṇu.
It supports the householder/royal duty of maintaining dharmic worship: performing orderly pūjā with prescribed mantras and observing sacred calendrical timing (nakṣatra-based observances).
Ritually, it prescribes aṅga-pūjā/nyāsa-style worship—assigning specific Viṣṇu epithets to body parts (waist, sides) and recommending worship on specific nakṣatras (Kṛttikā, the two Bhādrapadās), useful for temple liturgy and home pūjā scheduling.