Narada Purana — Purva Bhaga, Shloka 11
Tithi-Nirṇaya for Vratas: Ekādaśī Rules, Saṅkrānti Punya-kāla, Eclipse Observances, and Prāyaścitta
प्रदोषव्यापिनी ग्राह्या त्वन्यथा निष्फलं भवेत् । अर्द्धरात्रादधो या तु नक्षत्रव्यापिनी तिथिः ॥ ११ ॥
pradoṣavyāpinī grāhyā tvanyathā niṣphalaṃ bhavet | arddharātrādadho yā tu nakṣatravyāpinī tithiḥ || 11 ||
ينبغي اعتماد التِّثي التي تمتدّ خلال زمن البرَدوشا (pradoṣa)، وإلا صار العمل بلا ثمرة. أمّا التِّثي التي، بعد انقضاء منتصف الليل، تمتدّ إلى الجزء الأخير من الليل وهي شاملة للنَّكشترة، فهي المعتمدة والراجحة.
Sanatkumara (in dialogue instruction to Narada on observance rules)
Vrata: none
Primary Rasa: shanta
Secondary Rasa: bhayanaka
FAQs
It teaches that devotion and ritual observance must be aligned with correct sacred time (kāla); if the tithi is wrongly chosen, the intended spiritual fruit of the vrata or pūjā is said to be lost.
Bhakti is expressed through disciplined observance; the verse emphasizes that sincere worship is supported by proper vrata-timing—showing that devotion is not only emotion but also careful adherence to dharma-based procedure.
Jyotiṣa (Vedāṅga astrology): selecting the operative tithi by its extension through pradoṣa and by its overlap with nakṣatra, including the rule referencing the post-midnight portion of the night.