Matsya Purana — Description of the Akṣaya Tṛtīyā Observance
तृतीयायां समभ्यर्च्य सोपवासो जनार्दनम् राजसूयफलं प्राप्य गतिमग्र्यां च विन्दति //
tṛtīyāyāṃ samabhyarcya sopavāso janārdanam rājasūyaphalaṃ prāpya gatimagryāṃ ca vindati //
On the third lunar day (Tṛtīyā), one who worships Lord Janārdana while observing a fast (upavāsa) attains the merit of the Rājasūya sacrifice and also obtains the highest state (supreme liberation).
This verse does not address Pralaya; it teaches ritual merit—fasting and worship of Janārdana on the third tithi yields exalted spiritual results.
It offers a practical dharma-path: instead of undertaking an immense royal rite like the Rājasūya, a king or householder may gain comparable merit through disciplined fasting and devoted worship of Vishnu.
The ritual significance is tithi-based worship: performing Janārdana-pūjā on Tritīyā with upavāsa is prescribed as a high-merit observance, equated with the fruit of a major Vedic sacrifice.