Matsya Purana — Cosmic Architecture of Sun–Moon and the ‘Houses of the Gods’
ब्रह्मणा निर्मितं स्थानं तृतीयं तु तमोमयम् आदित्यात्स तु निष्क्रम्य सोमं गच्छति पर्वसु //
brahmaṇā nirmitaṃ sthānaṃ tṛtīyaṃ tu tamomayam ādityātsa tu niṣkramya somaṃ gacchati parvasu //
The third station—fashioned by Brahmā—is of the nature of darkness. Departing from the Sun, he proceeds to the Moon at the parvans, the lunar junctions.
It is primarily cosmological rather than pralaya-focused: it describes a Brahmā-created “third station” characterized by tamas (darkness) and a cyclic transition from the Sun toward the Moon at parvan junctions—imagery often used to map cosmic order rather than dissolution.
By highlighting parvan junctions as significant transition points, it indirectly supports dharmic timekeeping: kings and householders schedule vows, gifts, ancestral rites, and observances around lunar junctions (parvans), aligning social duty with cosmic rhythm.
Ritually, “parvan” is a key calendrical marker for ceremonies tied to the Moon’s phases (notably new/full moon and junction observances). Architecturally (Vastu), the verse is not prescriptive, but it contributes to the broader Matsya Purana habit of grounding ritual timing in cosmic movements.