Matsya Purana — Ekoddiṣṭa Śrāddha
त्रिभिः सपिण्डीकरणे अशेषत्रितये पिता यदा प्राप्स्यति कालेन तदा मुच्येत बन्धनात् //
tribhiḥ sapiṇḍīkaraṇe aśeṣatritaye pitā yadā prāpsyati kālena tadā mucyeta bandhanāt //
When, in due course of time, the father attains the complete triad through the three sapīṇḍīkaraṇa rites, then he is released from bondage (bandhana).
This verse does not address pralaya; it focuses on pitṛ-dharma—how prescribed ancestral rites (sapīṇḍīkaraṇa) lead to the departed father’s release from a binding post-death condition.
It highlights the gṛhastha obligation to perform śrāddha and sapīṇḍīkaraṇa correctly and in sequence; these rites are presented as efficacious for the welfare and liberation of one’s departed father/ancestors.
The significance is ritual (not architectural): sapīṇḍīkaraṇa is the rite that integrates the deceased into the ancestral piṇḍa lineage, and completing its prescribed threefold performance is said to remove “bondage” for the father.