Matsya Purana — Saptamī Sacred Bath and the Mṛtavatsābhiṣeka Rite for Pacifying Misfortune an...
कर्तुर्जन्मदिनर्क्षं च त्यक्त्वा सम्पूजयेत्सदा शान्त्यर्थं शुक्लसप्तम्याम् एतत्कुर्वन्न सीदति //
karturjanmadinarkṣaṃ ca tyaktvā sampūjayetsadā śāntyarthaṃ śuklasaptamyām etatkurvanna sīdati //
Setting aside (ordinary) attention to the patron’s birthday and birth-star (nakṣatra), one should always perform full worship for the sake of pacification on the bright fortnight’s seventh lunar day (Śukla-saptamī). One who performs this does not fall into distress.
This verse is not about pralaya; it teaches a śānti-oriented vrata: worship on Śukla-saptamī to avert distress and misfortune.
It frames dharmic timekeeping for patrons (kartuḥ): rather than centering rites only on personal birthday/birth-star, one should follow prescribed tithi-based observances (Śukla-saptamī) for public and personal well-being (śānti).
The ritual significance is calendrical: it prioritizes Śukla-saptamī as an auspicious tithi for complete pūjā aimed at pacification (śānti), indicating that correct timing is a key component of effective ritual practice.