Tithi-Nirṇaya for Vratas: Ekādaśī Rules, Saṅkrānti Punya-kāla, Eclipse Observances, and Prāyaścitta
क्षये पूर्वा प्रशस्ता स्याद्रृद्धौ कार्या तथोत्तरा । अर्ध्दरात्रद्वयव्यात्पा तिथिर्नक्षत्रसंयुता ॥ १४ ॥
kṣaye pūrvā praśastā syādrṛddhau kāryā tathottarā | ardhdarātradvayavyātpā tithirnakṣatrasaṃyutā || 14 ||
तिथि के क्षय में पूर्वभाग शुभ है और तिथि की वृद्धि में उत्तरभाग से कर्म करना चाहिए। जो तिथि नक्षत्र के साथ मिलकर दो अर्धरात्रियों तक व्याप्त हो, उसे मुहूर्त-निर्णय में मानें।
Narada (teaching traditional kala-nirnaya/auspicious time rules in the Narada Purana’s technical guidance)
Vrata: none
Primary Rasa: shanta
Secondary Rasa: none
It teaches dharmic precision in worship: selecting the correct portion of time (kāla) aligns a rite with cosmic order, making vrata, pūjā, and saṁskāra more effective and free from timing दोष (doṣa).
Bhakti is not only feeling but also disciplined practice; by observing proper tithi and nakṣatra timing, a devotee honors sacred order and performs devotion with care, steadiness, and scriptural alignment.
Jyotiṣa Vedāṅga (astronomical/astrological timekeeping): it gives a rule for choosing the earlier or later part of a tithi depending on kṣaya (decline) or vṛddhi (increase), and notes special consideration when a tithi spans two midnights along with nakṣatra association.