Matsya Purana — Yayāti and His Sons: The Exchange of Youth and Old Age
प्रतिपत्स्यामि ते राजन् पाप्मानं जरया सह गृहाण यौवनं मत्तश् चर कामान् यथेप्सितान् //
pratipatsyāmi te rājan pāpmānaṃ jarayā saha gṛhāṇa yauvanaṃ mattaś cara kāmān yathepsitān //
O King, I shall take upon myself your sin together with your old age; take my youth from me, and enjoy the pleasures you desire as you wish.
This verse does not discuss Pralaya; it focuses on personal karma and the moral consequences of desire, framed through the motif of transferring old age and sin.
It warns that indulgence in kāma has ethical and karmic weight; a king’s pursuit of pleasure is not value-neutral, and responsible rulership ideally restrains desire rather than shifting its burden onto others.
No Vāstu, temple-building, or ritual procedure is mentioned; the verse is narrative-ethical rather than architectural.