Narada Purana — Purva Bhaga, Shloka 100
The Exposition of the Dvādaśī Vow for the Twelve Months
Dvādaśī-vrata-nirṇaya and Mahā-dvādaśī Lakṣaṇas
यदोदये तु सवितुर्याम्या त्वेकादशीं स्पृशेत् । तदा वंजुलिकाख्यां तु तां त्यक्त्वोपोषयेत्सदा ॥ १०० ॥
yadodaye tu savituryāmyā tvekādaśīṃ spṛśet | tadā vaṃjulikākhyāṃ tu tāṃ tyaktvopoṣayetsadā || 100 ||
しかし、日の出の時に「ヤーミヤー」（南方）のティティがエーカーダシーに触れて重なるなら、そのエーカーダシーはヴァンジュリカー（Vaṃjulikā）と呼ばれ、これを退け、常に正しい日にウパヴァーサ（斎戒・断食）を守るべきである。
Sanatkumara (in instruction to Narada, Ekadashi-vrata rules)
Vrata: Ekādaśī (Vaṃjulikā)
Primary Rasa: shanta
Secondary Rasa: bhakti
FAQs
It emphasizes purity and precision in vrata-observance: Ekādaśī should be kept on the correctly determined day, because the spiritual fruit of the fast depends on proper tithi-nirṇaya (calendar correctness), not merely on intention.
By instructing how to correctly observe Ekādaśī upavāsa, it supports disciplined Vishnu-bhakti—devotion expressed through regulated vows (vrata), restraint, and faithful adherence to scriptural timing.
It reflects Jyotiṣa/Vedic calendrics (pañcāṅga principles): determining tithi contact at sunrise and rejecting a technically unsuitable Ekādaśī (Vaṃjulikā) to choose the proper fasting day.