Matsya Purana — Yuga Durations
विप्राः स्थिता धर्मपरा राजवृत्तौ स्थिता नृपाः कृष्यामभिरता वैश्याः शूद्राः शुश्रूषवः स्थिताः //
viprāḥ sthitā dharmaparā rājavṛttau sthitā nṛpāḥ kṛṣyāmabhiratā vaiśyāḥ śūdrāḥ śuśrūṣavaḥ sthitāḥ //
Brahmins remain firmly devoted to dharma; kings remain established in the proper conduct of rule; Vaishyas remain engaged in agriculture; and Shudras remain steady in service and attendance.
This verse is not about Pralaya; it describes social stability through each varna adhering to its dharma, a theme tied to sustaining order in the world.
It frames righteous kingship (rājavṛtti) as a stabilizing pillar of society, alongside household-based livelihoods like agriculture for Vaishyas and service-oriented duties for Shudras, with Brahmins upholding dharma.
No direct Vastu/temple-architecture rule is stated here; the verse instead provides a dharmic template of social roles that underlies ritual and civic order in the Purana’s broader teaching.