एवं त्रयोदशं यावन् मासमेवं द्विजोत्तमान् तर्पयेत यथाकामं प्रोषिते ऽन्यं समाचरेत् //
evaṃ trayodaśaṃ yāvan māsamevaṃ dvijottamān tarpayeta yathākāmaṃ proṣite 'nyaṃ samācaret //
وهكذا، طوال ثلاثة عشر شهرًا، عليه—بحسب رغبته وقدرته—أن يقدّم «تَرْپَنَة» (سكبَ الماء قربانًا) لأفاضل ذوي الولادتين. فإن كان الشخصُ الرئيس مسافرًا غائبًا، فليُجرِ الشعيرةَ لبديلٍ آخرَ لائق.
This verse does not discuss pralaya; it focuses on dharma in the form of tarpana/ancestral rites and their observance over a prescribed period.
It frames a householder’s (and by extension a ruler’s) obligation to maintain ritual continuity—performing tarpana over a defined cycle and ensuring the rite is still carried out even if the principal person is away by appointing an eligible substitute.
The significance is ritual: it prescribes the duration (up to thirteen months) and the contingency rule (if the intended person is absent, perform it with another qualified participant/recipient) for proper tarpana observance.