Narada Purana — Purva Bhaga, Shloka 43
Dvādaśī-vrata: Month-by-month Viṣṇu Worship and the Year-End Udyāpana
गोमेधमखजं पुण्यं सम्पूर्णं लभते नरः । चैत्रमासे सिते पक्षे द्वादश्यां समुपोषितः ॥ ४३ ॥
gomedhamakhajaṃ puṇyaṃ sampūrṇaṃ labhate naraḥ | caitramāse site pakṣe dvādaśyāṃ samupoṣitaḥ || 43 ||
凡于凯特罗月（Caitra）上半月光明分之第十二日（Dvādaśī）如法持斋者，得圆满功德，等同于修行“牛祭”（Go-medha）所生之福。
Narada
Vrata: Dvadashi-vrata (fasting on Dvādaśī; likely within a Viṣṇu-vrata sequence)
Primary Rasa: bhakti
Secondary Rasa: shanta
FAQs
It elevates a simple, accessible vrata—fasting on Caitra-śukla Dvādaśī—by declaring it yields the full merit of a major Vedic sacrifice, showing that disciplined observance can substitute for costly rituals.
By valuing fasting on an auspicious tithi (commonly associated with Vaiṣṇava observances), the verse frames bodily restraint and sacred-time discipline as supportive practices that deepen devotion and purity of mind.
It relies on calendrical precision—month (Caitra), fortnight (śukla pakṣa), and tithi (Dvādaśī)—reflecting practical Jyotiṣa-style timekeeping used to schedule vrata and ritual observances.