Matsya Purana — Pṛthu
दुहितृत्वं गता यस्मात् पृथोर्धर्मवतो मही तदानुरागयोगाच्च पृथिवी विश्रुता बुधैः //
duhitṛtvaṃ gatā yasmāt pṛthordharmavato mahī tadānurāgayogācca pṛthivī viśrutā budhaiḥ //
Because the Earth (mahī) came to be regarded as the daughter of the righteous King Pṛthu, and because of the bond of affection that arose thereby, she became renowned among the wise as “Pṛthivī.”
This verse does not describe Pralaya; it preserves an etymological tradition explaining Earth’s name “Pṛthivī” through her relationship with King Pṛthu.
By praising Pṛthu as “dharmavat” (righteous), the verse implies that a king’s legitimacy rests on dharma and benevolent guardianship—so much so that the land itself is symbolically linked to him as a ‘daughter’ under his protection.
No direct Vāstu or ritual rule appears here; the takeaway is conceptual—Earth (Pṛthivī) is sanctified through dharmic kingship, a worldview that underlies later temple/land rites where the ground is treated as revered and protected.