Matsya Purana — Manvantaras
प्रवर्तते तथा ते तु यथा मत्स्योदकावुभौ चेतनाधिकृतं सर्वं प्रावर्तत गुणात्मकम् कार्यकारणभावेन तथा तस्य प्रवर्तते //
pravartate tathā te tu yathā matsyodakāvubhau cetanādhikṛtaṃ sarvaṃ prāvartata guṇātmakam kāryakāraṇabhāvena tathā tasya pravartate //
So too do they function—just as fish and water exist in mutual dependence. In the same way, all that is constituted of the guṇas comes into operation when presided over by consciousness (cetanā), and it proceeds according to the relation of cause and effect; thus does its activity unfold.
It explains that the guṇa-made world-process (prakṛti and its evolutes) does not operate independently; it becomes active only when presided over by consciousness, and it unfolds through orderly cause-and-effect—an idea used in the Purana to frame both manifestation (sarga) and withdrawal (pralaya) as governed processes.
By emphasizing dependable causation (kārya–kāraṇa), it supports the ethical logic that actions produce results; hence a king or householder should act with dharma-aware intention, knowing governance, charity, ritual, and restraint yield corresponding outcomes.
No direct Vāstu or temple rule is stated; the takeaway is conceptual: rituals and constructions are also ‘cause-and-effect’ systems—proper intention (cetanā), correct procedure, and right materials lead to stable, auspicious results, aligning with later Matsya Purana Vastu Shastra tips.