Matsya Purana — Yadu Lineage
वयं तपश्चरिष्यामः संवृता वल्कलैर्वने प्रह्लादस्य वचः श्रुत्वा सत्याभिव्याहृतं तु तत् //
vayaṃ tapaścariṣyāmaḥ saṃvṛtā valkalairvane prahlādasya vacaḥ śrutvā satyābhivyāhṛtaṃ tu tat //
“We shall undertake austerities, clothed in bark-garments in the forest.” Having heard Prahlāda’s words, they accepted that utterance as a truthfully spoken resolve.
This verse does not describe Pralaya; it emphasizes ethical-spiritual discipline—undertaking tapas in the forest and the authority of a truthfully spoken resolve.
It reflects the broader dharma ideal that discipline and truthfulness are binding: a householder or king should honor truthful vows and, when appropriate, support or adopt regulated austerity (tapas) as a means of self-governance and moral integrity.
No Vāstu or temple-architecture rule appears here; the ritual takeaway is the ascetic observance—forest dwelling with bark garments as an emblem of renunciation and vow-based practice.