Matsya Purana — Ravi-Saṅkrānti Vow: Udyāpana
मार्तण्डमुत्तरे विष्णुम् ईशाने विन्यसेत्सदा गन्धमाल्यफलैर्भक्ष्यैः स्थण्डिले पूजयेत्ततः //
mārtaṇḍamuttare viṣṇum īśāne vinyasetsadā gandhamālyaphalairbhakṣyaiḥ sthaṇḍile pūjayettataḥ //
One should always place Mārtaṇḍa (the Sun) in the northern direction, and Viṣṇu in the north-east (Īśāna). Thereafter, on a prepared earthen altar (sthaṇḍila), one should worship them with perfumes, garlands, fruits, and edible offerings.
This verse is not about Pralaya; it gives practical ritual instructions—directional placement of deities (Surya and Vishnu) and their worship with standard offerings.
It frames a householder/royal duty as correct performance of worship: installing deities according to prescribed directions and offering gandha, garlands, fruits, and food—supporting dharma through orderly, rule-based ritual.
It encodes Vastu-linked ritual mapping: north and north-east placements (uttara, īśāna) and worship on a sthaṇḍila (purified earthen altar), reflecting how sacred space is organized before puja.