Matsya Purana — Inquiry into Taraka’s Slaying and the Prelude to Guha
वर्तन्त्या नियमे तस्याः सहस्राक्षः समाहितः उपासामाचरत्तस्याः सा चैनमन्वमन्यत //
vartantyā niyame tasyāḥ sahasrākṣaḥ samāhitaḥ upāsāmācarattasyāḥ sā cainamanvamanyata //
While she was steadfastly observing that sacred discipline, Sahasrākṣa (Indra), composed and intent, began to attend upon her with reverent service; and she, in turn, accepted him with favor.
This verse does not describe Pralaya; it highlights the potency of niyama (vowed discipline) and how even a major deity like Indra responds through composed, reverent attendance.
It models dharmic conduct: self-restraint (samāhita) and respectful service (upāsā) toward a virtuous person. For kings and householders, it implies that influence should be exercised through humility and disciplined behavior rather than force.
Architectural rules are not mentioned; ritually, the key term is upāsā—devotional attendance/service—paired with niyama, indicating that disciplined observance and proper reverence are central to effective religious practice.