Matsya Purana — Manvantaras
वत्सरो नग्नहूश् चैव भरद्वाजश्च वीर्यवान् ऋषिर्दीर्घतमाश्चैव बृहद्वक्षाः शरद्वतः //
vatsaro nagnahūś caiva bharadvājaśca vīryavān ṛṣirdīrghatamāścaiva bṛhadvakṣāḥ śaradvataḥ //
Also named are Vatsara and Nagnahū, and the mighty sage Bharadvāja; likewise the sage Dīrghatamas, and Bṛhadvakṣa, and Śaradvata.
This verse does not describe Pralaya directly; it preserves a genealogical catalogue of sages, emphasizing continuity of sacred knowledge across ages.
By naming authoritative ṛṣis, the text implicitly grounds dharma in recognized seer-traditions—kings and householders are expected to follow rites and ethics transmitted through such lineages.
No explicit Vāstu or temple rule appears in this verse; its ritual value lies in anchoring later prescriptions to revered ṛṣi authorities (e.g., Bharadvāja and other seers) cited across Purāṇic and śāstric traditions.