Matsya Purana — The Viśokā-Saptamī Vow
अतैललवणं भुक्त्वा सप्तम्यां मौनसंयुतः ततः पुराणश्रवणं कर्तव्यं भूतिमिच्छता //
atailalavaṇaṃ bhuktvā saptamyāṃ maunasaṃyutaḥ tataḥ purāṇaśravaṇaṃ kartavyaṃ bhūtimicchatā //
On Saptamī, having eaten food prepared without oil and salt, and observing silence, one who desires prosperity should then undertake the listening of the Purāṇa.
This verse does not discuss pralaya directly; it teaches a dharmic observance—dietary restraint, silence, and Purāṇa-listening—as a means to attain bhūti (worldly welfare/prosperity).
It frames a practical dharma for disciplined living: a householder (and by extension a ruler) cultivates self-control through regulated food and speech, then supports and participates in Purāṇa-śravaṇa—public religious instruction that reinforces ethical governance and social order.
The ritual significance is the prescribed Saptamī discipline—salt-and-oil-free food (ataila-lavaṇa), mauna (silence), and Purāṇa-śravaṇa—indicating a structured preparatory regimen before sacred hearing/recitation.