Narada Purana — Purva Bhaga, Shloka 19
Śrāddha-prayoga: Niyama, Brāhmaṇa-parīkṣā, Kutapa-kāla, Tithi-nyāya, and Vaiṣṇava-phala
निंमत्रयीत पूर्वेद्युस्तस्मिन्नेव दिनेऽथवा । निमंत्रितो भवेद्विप्रो ब्रह्मचारी जितेंद्रियः ॥ १९ ॥
niṃmatrayīta pūrvedyustasminneva dine'thavā | nimaṃtrito bhavedvipro brahmacārī jiteṃdriyaḥ || 19 ||
应在前一日或当日发出邀请。受邀的婆罗门当为梵行者（brahmacārī），自持克己，制伏诸根。
Narada (teaching in a dharma/ācāra context; dialogue framed within the Narada–Sanatkumara tradition)
Vrata: none
Primary Rasa: shanta
Secondary Rasa: none
FAQs
It emphasizes that ritual acts gain sanctity through right procedure (ācāra): timely invitation and the moral-spiritual fitness of the officiant, especially self-restraint and brahmacarya.
By insisting on purity of conduct and disciplined senses in those serving sacred acts, it supports bhakti as disciplined worship—devotion is strengthened when offerings and services are performed with inner restraint and reverence.
Kalpa (ritual procedure) is implied: formal invitation (nimantraṇa), correct timing, and qualification of the priest/participant are practical rules that preserve the correctness of rites.