Matsya Purana — Description of Gomedaka and Puṣkara Dvīpas; the Lokāloka Boundary; Ocean Tide...
अन्यूनानतिरिक्तात्मा वर्धन्त्यापो ह्रसन्ति च उदये ऽस्तमये चेन्दोः पक्षयोः शुक्लकृष्णयोः //
anyūnānatiriktātmā vardhantyāpo hrasanti ca udaye 'stamaye cendoḥ pakṣayoḥ śuklakṛṣṇayoḥ //
Neither deficient nor excessive in its own nature, the waters increase and also diminish according to the Moon’s rising and setting, through the bright and dark fortnights.
It frames nature as governed by orderly periodic cycles: even the waters rise and fall in step with lunar phases, implying cosmic regulation rather than randomness—an idea that underlies Purāṇic views of larger cycles like pralaya.
It supports choosing proper ritual times (śukla/kṛṣṇa pakṣa) for vows, offerings, and observances; a king or householder is expected to align dharmic acts with calendrical and cosmic rhythms taught in Purāṇic tradition.
Ritually, it emphasizes pakṣa-based timing (waxing/waning) relevant to vratas, śrāddha, and temple worship calendars; architecturally it is indirect, but such calendrical rules often guide temple consecrations and festival scheduling.