Matsya Purana — Yadu Lineage
त्रैलोक्यमिदमव्यग्रं महेन्द्रेणानुपाल्यते असपत्नमिदं सर्वम् आसीद्दशयुगं पुनः //
trailokyamidamavyagraṃ mahendreṇānupālyate asapatnamidaṃ sarvam āsīddaśayugaṃ punaḥ //
This threefold world remained untroubled, being protected by Mahendra (Indra). All of it was without any rival, and again it endured so for ten yugas.
It does not describe Pralaya directly; it highlights a stable cosmic phase where the three worlds remain undisturbed under Indra’s protection for an extended yuga-span.
By presenting Indra as the protector who keeps the worlds “unagitated,” it implies the royal ideal of governance: maintaining security, order, and freedom from conflict—an archetype for human kingship and social stability.
No explicit Vastu or ritual rule appears in this verse; its relevance is indirect—temple/ritual life is portrayed as flourishing best when the realm is protected and free from disturbance.