Matsya Purana — Solar–Lunar Motions
संध्यामुहूर्तमात्रायां ह्रासवृद्धी तु ते ऋते लेखाप्रभृत्यथादित्ये त्रिमुहूर्तागते तु वै //
saṃdhyāmuhūrtamātrāyāṃ hrāsavṛddhī tu te ṛte lekhāprabhṛtyathāditye trimuhūrtāgate tu vai //
Within the span of only one sandhyā-muhūrta, there is neither diminution nor increase in its effect. But beginning from “writing” and the like, when the Sun has advanced by three muhūrtas, the result indeed changes, showing decrease or increase.
This verse is not about Pralaya; it belongs to muhurta-vicāra, explaining how results are assessed by time—especially the twilight period and the Sun’s progression.
It guides kings and householders in choosing proper timing for commencements (e.g., administrative acts like writing/record-keeping, vows, and undertakings), emphasizing that timing after the Sun advances by three muhūrtas can alter outcomes.
It is a practical muhurta rule used in Vastu and ritual planning: during the sandhyā-muhūrta the stated effect is stable, while after three muhūrtas from a solar point, the auspicious/inauspicious strength may increase or decrease—affecting when to begin works like documentation, rites, or construction-related procedures.