Matsya Purana — Hiranyakashipu’s Boons
नरस्य कृत्वार्धतनुं सिंहस्यार्धतनुं तथा नारसिंहेन वपुषा पाणिं संस्पृश्य पाणिना //
narasya kṛtvārdhatanuṃ siṃhasyārdhatanuṃ tathā nārasiṃhena vapuṣā pāṇiṃ saṃspṛśya pāṇinā //
Fashioning half the body as that of a man and half as that of a lion, (the image) should be made with the Narasiṃha form, with one hand touching (or clasping) the other hand.
This verse does not discuss Pralaya; it gives a technical iconographic instruction for depicting Narasiṃha as half-man and half-lion with a specific hand-touching gesture.
Indirectly, it supports dharma through correct worship: kings and householders were expected to commission, install, and honor properly formed images in temples and shrines according to śāstric rules.
It specifies a pratima-lakṣaṇa (image-feature): Narasiṃha should be sculpted with a half-man/half-lion body and a prescribed hand contact (a defined pose/mudrā), guiding temple artists and ritual installers.