Matsya Purana — Soma
एवं ह्यविकलं श्राद्धं श्रद्धादत्तं मनुर्ब्रवीत् सनत्कुमारः प्रोवाच पश्यन्दिव्येन चक्षुषा //
evaṃ hyavikalaṃ śrāddhaṃ śraddhādattaṃ manurbravīt sanatkumāraḥ provāca paśyandivyena cakṣuṣā //
“Thus,” said Manu, “a śrāddha performed without defect and given with faith is truly efficacious.” Sanatkumāra proclaimed this as one who sees with divine vision.
This verse is not about Pralaya; it emphasizes ritual efficacy—Śrāddha becomes fruitful when it is complete (avikala) and performed with faith (śraddhā).
It supports gṛhastha-dharma: a householder (and by extension a king as guardian of dharma) should ensure Śrāddha is performed properly and with sincere faith, not merely as a formality.
The ritual takeaway is the key point: “avikala” indicates correctness and completeness in procedure—no missing steps, proper offering, and an inner attitude of śraddhā—rather than any Vāstu or temple-building rule.