Tithi-Nirṇaya for Vratas: Ekādaśī Rules, Saṅkrānti Punya-kāla, Eclipse Observances, and Prāyaścitta
संपूर्णैकादशी शुद्धा द्वादश्यां च प्रतीयते । त्रयोदशी च रात्र्यंते तत्र वक्ष्यामि निर्णयम् ॥ ४२ ॥
saṃpūrṇaikādaśī śuddhā dvādaśyāṃ ca pratīyate | trayodaśī ca rātryaṃte tatra vakṣyāmi nirṇayam || 42 ||
Quando a Ekādaśī está completa e pura, deve-se entendê-la como ligada à Dvādaśī; e se ela se estender até o fim da noite de Trayodaśī, então declararei a determinação correta para essa observância.
Sanatkumara (in dialogue with Narada)
Vrata: Ekadashi
Primary Rasa: shanta
Secondary Rasa: bhakti
It frames Ekādaśī as a dharmic vrata requiring correct timing (nirṇaya); purity of the tithi safeguards the spiritual merit of the vow and its Vishnu-oriented devotional purpose.
By emphasizing precise observance of Ekādaśī, it supports disciplined bhakti—devotion expressed through regulated fasting and adherence to sacred time, rather than mere sentiment.
Vedāṅga Jyotiṣa/Kalpa-style tithi-nirṇaya: recognizing when Ekādaśī is “śuddhā” and how to decide observance when it overlaps into Dvādaśī or even extends toward Trayodaśī night-end.