Matsya Purana — Solar Dynasty Prelude: Vivasvān–Saṃjñā–Chāyā
नारीमुत्पादयामास स्वशरीरादनिन्दिताम् त्वाष्ट्री स्वरूपरूपेण नाम्ना छायेति भामिनी //
nārīmutpādayāmāsa svaśarīrādaninditām tvāṣṭrī svarūparūpeṇa nāmnā chāyeti bhāminī //
From her own body she brought forth an irreproachable woman—Tvaṣṭrī in nature and in form—who was known by the name Chāyā, the radiant lady.
This verse is about creation (sarga) on a personal, mythic level—manifesting Chāyā from one’s own body—rather than cosmic dissolution (pralaya).
Indirectly, it supports the Purāṇic ideal of orderly lineage and righteous household continuity: the narrative frames how persons and relations arise in a regulated, ‘blameless’ manner, which later underpins dharma in family and kingship.
No direct Vāstu/temple rule is stated; the key technical idea is ‘form-making’ (tvāṣṭrī, linked with Tvaṣṭṛ), a concept later echoed in iconography and craftsmanship traditions rather than explicit building prescriptions here.