Matsya Purana — Dynastic Genealogies: Paurava–Anu Lines
प्राशितं यद्यदङ्गेषु न सोपस्थं शुचिस्मिते तेन तिष्ठन्ति ते गर्भे पौर्णमास्याम् इवोडुराट् //
prāśitaṃ yadyadaṅgeṣu na sopasthaṃ śucismite tena tiṣṭhanti te garbhe paurṇamāsyām ivoḍurāṭ //
Whatever food is taken in nourishes the limbs, yet not the region of the loins. O pure-smiling one, by that order of nourishment they remain established in the womb, like the lordly moon on the night of the full moon.
This verse is not about Pralaya; it uses a cosmic image (the full moon) as a metaphor to explain stability and established order within the womb during conception and development.
It supports the Matsya Purana’s broader householder ethic: disciplined conduct, purity, and regulated nourishment are presented as factors that sustain healthy conception and the stability of the embryo.
No Vastu or temple-architecture rule appears here; the ritual significance is indirect—emphasizing purity and proper intake as part of garbha-related observances within domestic dharma.