Matsya Purana — Bhīma-Dvādaśī
*वासुदेव उवाच यद्यष्टमीचतुर्दश्योर् द्वादशीष्वथ भारत अन्येष्वपि दिनर्क्षेषु न शक्तस्त्वम् उपोषितुम् //
*vāsudeva uvāca yadyaṣṭamīcaturdaśyor dvādaśīṣvatha bhārata anyeṣvapi dinarkṣeṣu na śaktastvam upoṣitum //
Vāsudeva said: O Bhārata, if you are not able to fast on the eighth and the fourteenth lunar days, or on the twelfth, or even on other specially marked days and lunar asterisms, then follow the suitable alternative discipline that will be taught.
This verse does not discuss Pralaya; it focuses on practical dharma—fasting (upoṣaṇa) tied to lunar dates (tithi) and nakṣatra-based observances.
It frames dharma as adaptable: if a person (including a householder or ruler) cannot keep demanding fasts on key tithis like Aṣṭamī, Caturdaśī, or Dvādaśī, the tradition allows graded observance and alternative disciplines rather than abandonment of religious duty.
Architectural topics are not present here; the ritual significance is the prioritization of specific tithis and nakṣatra-days for upavāsa (fasting) within Matsya Purana vrata practice.