Matsya Purana — Rasakalyāṇinī Vrata: Magha-based Goddess Worship
क्रमान्माघादि सर्वत्र प्रीयतामिति कीर्तयेत् सर्वत्र पञ्चगव्येन प्राशनं समुदाहृतम् उपवासी भवेन्नित्यम् अशक्ते नक्तमिष्यते //
kramānmāghādi sarvatra prīyatāmiti kīrtayet sarvatra pañcagavyena prāśanaṃ samudāhṛtam upavāsī bhavennityam aśakte naktamiṣyate //
Beginning in due order with the month of Māgha and continuing likewise throughout the cycle, one should recite, “May (the Lord) be pleased.” In every such observance, the prescribed act is the sipping/partaking of pañcagavya. One should regularly keep fasts; but if one is unable, then taking a single meal at night (naktabhojana) is permitted.
This verse does not discuss pralaya; it focuses on vrata-krama (monthly observance), purification via pañcagavya, and regulated fasting as a dharmic discipline.
It outlines a practical rule of conduct: maintain regular fasting and devotional recitation, use pañcagavya as a purificatory intake, and adopt an accessible alternative (one night meal) when strict fasting is not feasible—guidance suited to householders and rulers managing health and duty.
The significance is ritual: pañcagavya-prāśana is prescribed as a purification act within observances, and naktabhojana is given as an approved concession when full fasting cannot be maintained.