Matsya Purana — Solar–Lunar Motions
भूयो भूयः प्रवक्ष्यामि प्रमाणं चन्द्रसूर्ययोः महितत्वान्महच्छब्दो ह्य् अस्मिन्नर्थे निगद्यते //
bhūyo bhūyaḥ pravakṣyāmi pramāṇaṃ candrasūryayoḥ mahitatvānmahacchabdo hy asminnarthe nigadyate //
Again and again I shall declare the proper measure of the Moon and the Sun; because of their exalted greatness, the term “mahāt” (great) is indeed used here in this sense.
This verse does not describe Pralaya directly; it signals a cosmological-astronomical exposition, focusing on the fixed “measures” and exalted status of the Sun and Moon within the ordered universe.
Indirectly, it supports dharmic governance and household life by grounding ritual calendars (tithis, months, seasons) in the Sun–Moon framework; accurate knowledge of celestial measures underpins proper timing of vows, rites, and public ceremonies.
Ritually, Sun–Moon measures relate to calendrical reckoning used for yajña, dāna, and vrata timings; architecturally, such cosmological framing often informs temple orientation and sacred timekeeping, though no specific Vāstu rule is stated in this verse.