Matsya Purana — Śrāddha Procedure: Types
दक्षिणं जानुमालभ्य त्वं मया तु निमन्त्रितः एवं निमन्त्र्य नियमं श्रावयेत्पितृबान्धवान् //
dakṣiṇaṃ jānumālabhya tvaṃ mayā tu nimantritaḥ evaṃ nimantrya niyamaṃ śrāvayetpitṛbāndhavān //
Touching the right knee (as a respectful entreaty), one should say: “You have indeed been invited by me.” Having thus invited them, one should then make the rule of observance heard by the paternal relatives.
This verse does not discuss Pralaya; it gives a practical rule of ritual etiquette for inviting paternal relatives and communicating the observances to be followed.
It aligns with gṛhastha-dharma: a householder must perform Pitṛ-related rites properly, including formally inviting eligible relatives and clearly stating the niyamas (disciplinary rules) to ensure the rite is conducted in a pure and orderly manner.
The significance is ritual, not architectural: it prescribes the respectful invitation gesture (touching the right knee) and the requirement to announce the observance-rules to the paternal kin before the rite proceeds.