Matsya Purana — Prayaga Mahatmya: Trimurti Presence
*मार्कण्डेय उवाच शृणु राजन्प्रयागे तु प्रोक्तं सर्वमिदं जगत् ब्रह्मा विष्णुस्तथेशानो देवताः प्रभुरव्ययः //
*mārkaṇḍeya uvāca śṛṇu rājanprayāge tu proktaṃ sarvamidaṃ jagat brahmā viṣṇustatheśāno devatāḥ prabhuravyayaḥ //
Mārkaṇḍeya said: “Listen, O King—at Prayāga this entire world is spoken of (and made manifest): Brahmā, Viṣṇu, and likewise Īśāna (Śiva)—the deities—the imperishable Lord.”
It does not narrate Pralaya directly; it frames Prayāga as a supreme sacred locus where the cosmic principles represented by Brahmā (creation), Viṣṇu (preservation), and Īśāna/Śiva (dissolution) are acknowledged together.
By addressing the listener as “O King,” the verse positions pilgrimage and attentive hearing of tīrtha-mahātmyas as part of rājadarma—cultivating dharma through reverence to holy places and honoring the divine order embodied by the major deities.
No explicit Vāstu or iconographic rule is stated; the ritual takeaway is the primacy of Prayāga as a tīrtha where worship/recitation is understood to connect one to the Trimūrti and the imperishable Lord.