Matsya Purana — Cosmography of Śākadvīpa and Successive Dvīpas: Mountains
तेनावृतः समुद्रो ऽयं द्वीपेन लवणोदधिः तत्र पुण्या जनपदाश् चिराच्च म्रियते जनः //
tenāvṛtaḥ samudro 'yaṃ dvīpena lavaṇodadhiḥ tatra puṇyā janapadāś cirācca mriyate janaḥ //
Encircled by that island-continent, this salt ocean is enclosed. There, the settled regions are holy, and people die only after a very long span of life.
This verse is not describing pralaya; it presents cosmography—how the salt ocean is bounded by a dvīpa—and notes the auspicious nature of the lands there, including long human lifespan.
By calling certain janapadas “puṇya,” it implies that righteous living, protection of sacred lands, and sustaining dharmic society in one’s territory are merit-producing—an indirect guideline for kings (good governance) and householders (dharmic residence and conduct).
No direct Vāstu or ritual procedure is stated; however, the verse frames certain regions as intrinsically sacred (puṇya-janapada), a common basis in Purāṇas for choosing auspicious sites for settlement, temples, and rites.