Matsya Purana — Account of the Manvantaras: Manus
एकचित्तः प्रशान्तात्मा शृणु मार्तण्डनन्दन यामा नाम पुरा देवा आसन् स्वायम्भुवान्तरे //
ekacittaḥ praśāntātmā śṛṇu mārtaṇḍanandana yāmā nāma purā devā āsan svāyambhuvāntare //
With a single-pointed mind and a composed inner self, listen, O son of Mārtaṇḍa (the Sun): in ancient times, during the Svāyambhuva Manvantara, there existed deities known as the Yāmas.
It situates the teaching within cyclic time (Manvantaras), implying an ordered cosmic chronology rather than describing Pralaya directly; it points to how different divine classes appear in different eras.
The instruction “single-minded and calm, listen” models the ideal discipline of a ruler/student: attentive śravaṇa (listening) and inner restraint—foundational virtues for righteous governance and household ethics in Purāṇic guidance.
No explicit Vāstu or ritual procedure is stated; the verse functions as a narrative preface establishing cosmological context (Manvantara and deva-groups) that later supports ritual timing and tradition-based authority.