Matsya Purana — Solar Dynasty Prelude: Vivasvān–Saṃjñā–Chāyā
यमुना तपती चैव पुनर्नद्यौ बभूवतुः विष्टिर्घोरात्मिका तद्वत् कालत्वेन व्यवस्थिता //
yamunā tapatī caiva punarnadyau babhūvatuḥ viṣṭirghorātmikā tadvat kālatvena vyavasthitā //
Yamunā and Tapatī again became rivers; likewise Viṣṭi—of dreadful nature—was established in the same manner, as an embodiment of Time (Kāla).
It frames natural and astral forces as being re-ordered under Kāla (Time), suggesting that even rivers and inauspicious powers like Viṣṭi become instruments through which dissolution and cosmic transition are administered.
By highlighting Viṣṭi’s dreadful character and Kāla’s governance, it supports the Purāṇic ethic of choosing auspicious times for major acts (royal decisions, rites, journeys) and maintaining dharmic discipline when ominous time-signs prevail.
Ritually, Viṣṭi is traditionally treated as inauspicious for commencements; the verse reinforces time-selection (muhūrta) principles relevant to temple-building, consecrations, and other Vastu Shastra–aligned undertakings.