Matsya Purana — Measures of Time: Caturyuga Computation
पुत्रपौत्रसमाकीर्णा म्रियन्ते च क्रमेण ताः एष त्रेतायुगे भावस् त्रेतासंख्यां निबोधत //
putrapautrasamākīrṇā mriyante ca krameṇa tāḥ eṣa tretāyuge bhāvas tretāsaṃkhyāṃ nibodhata //
Surrounded by sons and grandsons, they pass away in due succession. Such is the condition in the Tretā Yuga—now understand the reckoning (numbers) for the Tretā.
It does not directly describe Pralaya; it highlights orderly human succession and death in the Tretā Yuga, as part of the Purana’s broader time-cycle teaching.
By emphasizing dying “in due order” amid descendants, it upholds the householder ideal of sustaining lineage and social continuity—key supports for a king’s stable realm and for grihastha-dharma.
No Vāstu or ritual procedure is stated here; the verse is primarily about yuga-characteristics and chronological enumeration.