Tithi-Nirṇaya for Vratas: Ekādaśī Rules, Saṅkrānti Punya-kāla, Eclipse Observances, and Prāyaścitta
तस्यां तु तद्वतं कार्यं सैव कार्या विचक्षणैः । उदयव्यापिनी ग्राह्या श्रवणद्वादशी व्रते ॥ १८ ॥
tasyāṃ tu tadvataṃ kāryaṃ saiva kāryā vicakṣaṇaiḥ | udayavyāpinī grāhyā śravaṇadvādaśī vrate || 18 ||
Nesse mesmo tithi deve ser realizado o mesmo voto; os discernentes devem observá-lo naquele próprio dia. No voto de Śravaṇa-dvādaśī, deve-se aceitar a Dvādaśī que se estende até o nascer do sol (udaya-vyāpinī).
Sanatkumara (teaching Narada)
Vrata: Śravaṇa-dvādaśī-vrata
Primary Rasa: shanta
Secondary Rasa: none
It emphasizes disciplined, accurate observance of a Vaiṣṇava vrata: spiritual merit depends not only on devotion but also on correct timing (tithi-nirṇaya), especially for Śravaṇa Dvādaśī.
Bhakti here is expressed through faithful vrata-practice; the verse teaches that a devotee should follow the śāstric rule—accepting the Dvādaśī that touches sunrise—so worship and fasting align with dharma.
It highlights calendrical/astronomical decision-making used in ritual timing (tithi determination)—a practical application associated with Jyotiṣa-based vrata scheduling (udaya-vyāpinī tithi rule).