Srimad Bhagavatam — Shashtha Skandha, Shloka 6
Nārāyaṇa-kavaca — The Armor of Lord Nārāyaṇa
श्रीविश्वरूप उवाच धौताङ्घ्रिपाणिराचम्य सपवित्र उदङ्मुख: । कृतस्वाङ्गकरन्यासो मन्त्राभ्यां वाग्यत: शुचि: ॥ ४ ॥ नारायणपरं वर्म सन्नह्येद् भय आगते । पादयोर्जानुनोरूर्वोरुदरे हृद्यथोरसि ॥ ५ ॥ मुखे शिरस्यानुपूर्व्यादोंङ्कारादीनि विन्यसेत् । ॐ नमो नारायणायेति विपर्ययमथापि वा ॥ ६ ॥
śrī-viśvarūpa uvāca dhautāṅghri-pāṇir ācamya sapavitra udaṅ-mukhaḥ kṛta-svāṅga-kara-nyāso mantrābhyāṁ vāg-yataḥ śuciḥ
毗湿瓦鲁帕说：在恐惧之时，应洗净手足，行净口以成清净；北向端坐，触库沙草而守默。随后以八字与十二字真言作安置（nyāsa），披戴那罗延护甲。诵“唵 那摩 那罗延那耶”时，从足至顶依次安置，再按逆序重行一遍。
FAQs
In this verse, the Bhagavatam describes a method of protective devotion using mantra-nyāsa—placing the syllables of “Oṁ namo nārāyaṇāya” on the mouth and head in proper sequence (or even in reverse), establishing remembrance of Nārāyaṇa as a spiritual shield.
Viśvarūpa teaches Indra a protective armor (kavacha) rooted in surrender to Nārāyaṇa; the mantra-nyāsa focuses the practitioner’s mind and senses on the Lord, invoking divine protection during danger.
Chant “Oṁ namo nārāyaṇāya” with attention, and mentally place the mantra on the head and mouth—offering your thoughts and speech to the Lord—especially before stressful tasks, travel, or moments of fear.