Tithi-Nirṇaya for Vratas: Ekādaśī Rules, Saṅkrānti Punya-kāla, Eclipse Observances, and Prāyaścitta
सैव ग्राह्या मुनिश्रेष्ट नक्षत्रविहितव्रते । यद्यर्द्धरात्रघगयोर्व्यात्पं नक्षत्रं तु दिनद्वये ॥ १२ ॥
saiva grāhyā muniśreṣṭa nakṣatravihitavrate | yadyarddharātraghagayorvyātpaṃ nakṣatraṃ tu dinadvaye || 12 ||
يا أفضلَ الحكماء، في النذر المقرَّر بالرجوع إلى نكشترةٍ معيّنة، لا يُعتَمَد إلا تلك النكشترة بعينها لتعيين وقت الأداء، ولو أنها بعد تجاوز منتصف الليل امتدّت على اليومين كليهما.
Sanatkumara (teaching Narada)
Vrata: none
Primary Rasa: shanta
Secondary Rasa: bhakti
It emphasizes dharma through precision in vrata observance: when a vow is tied to a nakṣatra, fidelity to the prescribed celestial marker preserves the intended merit (phala) of the rite.
By teaching careful observance of vow-timings, it supports disciplined devotional practice: correct ritual timing becomes a form of attentive service (sevā) offered with steadiness of mind.
Vedāṅga Jyotiṣa: it gives a rule for deciding the operative nakṣatra when it overlaps two civil days due to crossing midnight, guiding calendar-based ritual decisions.