Matsya Purana — The Ravi-Śayana
*नारद उवाच उपवासेष्वशक्तस्य तदेव फलमिच्छतः अनभ्यासेन रोगाद्वा किमिष्टं व्रतमुत्तमम् //
*nārada uvāca upavāseṣvaśaktasya tadeva phalamicchataḥ anabhyāsena rogādvā kimiṣṭaṃ vratamuttamam //
Nārada said: For one who is unable to undertake fasts, yet desires the same merit—whether from lack of practice or because of illness—what is the most excellent and acceptable vow (vrata) to observe?
This verse does not address pralaya; it focuses on dharma—how a devotee may still obtain religious merit when fasting is not feasible.
It frames a practical dharma question: householders (and rulers) must adapt religious observances to health and capacity, seeking an approved vow that preserves the intended spiritual merit without causing harm.
The ritual significance is the principle of “substitute observance” (an alternative vrata) when upavāsa is impossible, implying that intention and approved procedure can preserve the vow’s fruit.