Matsya Purana — Division of Bhārata-varṣa
जम्बूखण्डस्य विस्तारं तथान्येषां विदांवर द्वीपानां वासिनां तेषां वृक्षाणां प्रब्रवीहि नः //
jambūkhaṇḍasya vistāraṃ tathānyeṣāṃ vidāṃvara dvīpānāṃ vāsināṃ teṣāṃ vṛkṣāṇāṃ prabravīhi naḥ //
O best among the wise, tell us the extent of Jambū-khaṇḍa, and likewise of the other islands—their inhabitants and the trees that belong to them.
This verse is not about Pralaya; it introduces a cosmographic inquiry, asking for the measured extent of Jambūdvīpa and other dvīpas along with their inhabitants and characteristic trees.
Indirectly, it frames the kingly/householder ideal of learning: Manu seeks authoritative knowledge of the world’s layout and peoples, a kind of puranic “statecraft of understanding” that supports righteous governance and informed ritual life.
No direct Vāstu or ritual procedure is stated here; however, the focus on sacred trees and regional descriptions often underpins later ritual geography (tīrthas, sacred flora) and place-based sanctity used in temple and pilgrimage traditions.