मन्त्रराजं नारसिंहमानुष्टुभं प्रायच्छत्तेन वै स मृत्युमजयन्स पाप्मानमतरन्स सं- सारं चातरंस्तस्माद्यो मृत्योः पाप्मभ्यः संसाराच्च बिभीयात्स एतं मन्त्ररा- जं नारसिंहमानुष्टुभं प्रतिगृह्णीयात्स मृ- त्युं जयति स पाप्मानं तरति स संसारं तरति तस्य ह वै प्रणवस्य या पूर्वा मा- त्रा पृथिव्यकारः स ऋग्भिर्ऋग्वेदो ब्रह्मा वसवो गायत्री गार्हपत्यः सा साम्नः प्र- थमः पादो भवति द्वितीयान्तरिक्षं स उकारः स यजुर्भिर्यजुर्वेदो विष्णू रुद्रा- स्त्रिष्टुब्दक्षिणाग्निः सा साम्नो द्वितीयः पादो भवति तृतीया द्यौः स मकारः स सामभिः सामवेदो रुद्रा आदित्या जग- त्याहवनीयः सा साम्नस्तृतीयः पादो भ- वति यावसानेऽस्य चतुर्थ्यर्धमात्रा सा सोमलोक ओंकारः सोऽथर्वणैर्मन्त्रैरथ-र्ववेदः संवर्तकोऽग्निर्मरुतो विराडेक ऋ-षिर्भास्वती मा साम्नश्चतुर्थः पादोभवति ॥ १ ॥
In plain words
This is the mantra he gave him -- the king among mantras, the Nārasiṃha, set in the Anuṣṭubh metre. With it, he conquered death outright, he crossed clean over sin, and he crossed clean over the whole turning wheel of saṃsāra. So whoever is afraid -- of death, of sin, of that wheel -- let him take up this same king of mantras. Death, sin, saṃsāra: he crosses every one of them. Now look at what the Praṇava itself contains. Its first mora is the sound 'a', and it is the earth: the Ṛg verses, the Ṛgveda, Brahmā, the Vasus, the Gāyatrī metre, the household fire -- all of it gathered into the first quarter of this Sāma. Its second mora is the sound 'u', and it is the space between earth and sky: the Yajus verses, the Yajurveda, Viṣṇu, the Rudras, the Triṣṭubh metre, the southern fire -- the second quarter. Its third mora is the sound 'm', and it is the sky itself: the Sāman chants, the Sāmaveda, the Rudras, the Ādityas, the Jagatī metre, the offering-fire -- the third quarter. And what trails after, right to the close -- that faint half-mora -- is the world of Soma, the hum of Om itself: the Atharvan formulas, the Atharvaveda, the fire that gathers the world back into itself, the Maruts, the Virāj metre, the one seer, the radiant presence. That last breath of sound is the fourth quarter of the Sāma.
Close to the Sanskrit
[Prajāpati] gave [him] the king of mantras, the Nārasiṃha [mantra] in the Anuṣṭubh metre. By that indeed he conquered death, he crossed over sin, and he crossed over saṃsāra. Therefore, whoever should fear death, sins, and saṃsāra, let him take up this king of mantras, the Nārasiṃha in Anuṣṭubh -- he conquers death, he crosses over sin, he crosses over saṃsāra. Now, of that Praṇava, the first mora, which is the earth, is the sound 'a'; it, with the Ṛg [verses], [is] the Ṛgveda, Brahmā, the Vasus, the Gāyatrī, the Gārhapatya [fire] -- that is the first quarter of the Sāma. The second [mora] is the mid-region, the sound 'u'; it, with the Yajus [verses, is] the Yajurveda, Viṣṇu, the Rudras, the Triṣṭubh, the southern fire -- that is the second quarter of the Sāma. The third [mora] is the sky, the sound 'm'; it, with the Sāman [chants, is] the Sāmaveda, the Rudras, the Ādityas, the Jagatī, the Āhavanīya [fire] -- that is the third quarter of the Sāma. As far as the close of it, its fourth, the half-mora -- that is the world of Soma, the syllable Om; it, with the Atharvan formulas, [is] the Atharvaveda, the Saṃvartaka fire, the Maruts, the Virāj [metre], the sole seer, the radiant one -- this 'mā' is the fourth quarter of the Sāma.