Graha–Ketu–Utpāta Lakṣaṇas: Solar/Lunar Omens, Comets, Eclipses, and Calendar Rules
षण्मासवृद्ध्या ग्रहणं शोधयेद्र विचंद्र योः । पर्वेशास्तु तथा सत्यदेवा रव्यादितः क्रमात् ॥ ८१ ॥
ṣaṇmāsavṛddhyā grahaṇaṃ śodhayedra vicaṃdra yoḥ | parveśāstu tathā satyadevā ravyāditaḥ kramāt || 81 ||
六か月の補正を加えて、日食と月食を算定し、確かめるべきである。同様に、節目の日(パルヴァン)の主宰者たちも、太陽より始めて順次に定め、対応するサティヤ・デーヴァとともに確立すべきである。
Sanatkumara (in instruction to Narada within the Moksha-Dharma discourse, touching Vedanga-style calendrical science)
Vrata: none
Primary Rasa: shanta
Secondary Rasa: adbhuta
It links dharma to correct time-reckoning: sacred observances depend on accurate parvan and eclipse determination, so spiritual practice is aligned with cosmic order (ṛta).
Indirectly: bhakti-oriented vratas and worship performed on parvan days or during eclipse-related rites require proper calendrical knowledge; devotion is strengthened when worship is done at the right sacred times.
Vedāṅga Jyotiṣa: the verse indicates a rule of correction (six-month adjustment) for checking solar/lunar eclipses and determining parvan presiding deities in proper sequence.