Matsya Purana — The Ravi-Śayana
*ईश्वर उवाच उपवासे ऽप्यशक्तानां नक्तं भोजनमिष्यते यस्मिन्व्रते तदप्यत्र श्रूयतामक्षयं महत् //
*īśvara uvāca upavāse 'pyaśaktānāṃ naktaṃ bhojanamiṣyate yasminvrate tadapyatra śrūyatāmakṣayaṃ mahat //
Īśvara said: Even for those unable to keep a full fast, a single meal at night (nakta-bhojana) is permitted in that vow. Now hear of the great, imperishable merit that arises from it.
This verse does not address pralaya; it focuses on vrata-dharma, specifically compassionate allowances within fasting observances.
It frames dharma as practicable: a householder (and by extension a king guiding subjects) may permit nakta-bhojana for those unable to fast fully, preserving the vow’s intent while avoiding harm.
The ritual point is procedural: in a vrata, if strict fasting is not possible, a sanctioned substitute is a single night-meal, still said to yield “akṣaya” (enduring) religious merit.