Matsya Purana — Prayaga Mahatmya: Trimurti Presence
ब्रह्मा सृजति भूतानि स्थावरं जङ्गमं च यत् तान्येतानि परं लोके विष्णुः संवर्धते प्रजाः //
brahmā sṛjati bhūtāni sthāvaraṃ jaṅgamaṃ ca yat tānyetāni paraṃ loke viṣṇuḥ saṃvardhate prajāḥ //
Brahmā creates the beings—both the immovable and the movable; and in the higher world it is Viṣṇu who nurtures and causes these creatures (the progeny) to flourish.
It highlights the cosmic division of functions: Brahmā initiates creation (sṛṣṭi) of all beings, while Viṣṇu sustains and increases them (sthiti). Though Pralaya is not explicit here, the verse situates preservation as a distinct divine operation that counters decline.
By modeling Viṣṇu as the nourisher and increaser of prajā (creatures/subjects), it implies a dharmic ideal for rulers and householders: protect, support, and help dependents flourish—rather than merely producing or acquiring.
No direct Vāstu or ritual rule is stated; however, the verse supplies the theological basis often invoked in temple culture—Viṣṇu as the sustaining principle—supporting why preservation, upkeep, and daily worship (nitya-sevā) are central in ritual life.