Narada Purana — Purva Bhaga, Shloka 52
Tithi-Nirṇaya for Vratas: Ekādaśī Rules, Saṅkrānti Punya-kāla, Eclipse Observances, and Prāyaścitta
पूर्वा गृहस्थैः कार्यात्र यतिभिश्चोत्तरा तिथिः । उपोष्यैव द्वितीयेति केचिदाहुश्च भक्तितः ॥ ५२ ॥
pūrvā gṛhasthaiḥ kāryātra yatibhiścottarā tithiḥ | upoṣyaiva dvitīyeti kecidāhuśca bhaktitaḥ || 52 ||
在此，居家者（gṛhastha）应遵守较早的月日（tithi），而出家遁世者（yati）应遵守较后的月日。又有一些奉爱者出于对圣毗湿奴的奉爱（bhakti），说应当在第二日当日即行斋戒并修持此戒。
Sanatkumara (in instruction to Narada, within the vrata/tithi discussion)
Vrata: Ekadashi (contextual)
Primary Rasa: shanta
Secondary Rasa: bhakti
FAQs
It teaches that devotional observances must be aligned with dharma and eligibility: householders and renunciants may follow different tithi rules, yet the core aim remains sincere devotion expressed through disciplined fasting and observance.
Bhakti is shown as both rule-guided and heartfelt: while tithi selection follows tradition (earlier for gṛhasthas, later for yatis), some devotees emphasize devotion by fasting on the following day as well, prioritizing earnest worship and restraint.
It reflects Vedāṅga Jyotiṣa-style tithi-nirṇaya (lunar-day determination) used in vrata scheduling—how to choose the correct observance day when tithis shift, with different prescriptions based on āśrama (life-stage).