Bhashya
तच्छब्देन द्वात्रिंशदरं द्वात्रिंशत्पत्रं चक्रम् एवशब्देन तदे-वावधृत्य तदेव चक्रं तदादिन्यायेन सुदर्शनादिशब्दैरूर्ध्व चक्र-चतुष्टयमपि महाचक्रात्मकमिति दर्शयति ।महाचक्रमिति सा-मानाधिकरण्याच्च ।तस्य मध्ये महाचक्रस्य मध्ये मध्यवर्ति-नाभ्यां वेष्टनरूपा हि नाभयो भूमध्याः ताः व्यावर्तयितुं मध्येनाभ्यामित्युक्तम् ।तारकं भवति संसारतारकत्वात् तारकं प्रण-वाक्षरं भवति ।यदक्षरं नारसिंहमेकाक्षरं तद्वतीति अक्षरम् ,जगद्धितं वा एतद्रूपमक्षरमिति नृसिंहपदव्याख्यानावसरे व्या-ख्यातं तदक्षरशब्दात्प्रत्यभिज्ञायते ।तथा नारसिंहमितितद्धितात्सामप्रभृत्युपास्यं सर्वं प्रतीयते ।ततः सर्वस्मिन्नुपास्येप्रतीते एकमेवोपास्यं मूलनृसिंहव्यूहाख्यं वक्तुं विशिनष्टि—एकाक्षरं तद्वतीति ।यदक्षरं नारसिंहमुपास्यम् इत्यनूद्यतदेकं भवतीत्यक्षरं च इति महाचक्रमध्यनाभिवर्तित्वेन क्षीरो-दार्णवसंबन्धितया उपासनं विधीयत इत्यर्थः ।तत्र केचित् नारसिंहमेकाक्षरम् इति विशेषणोपादानात् एकाक्षरनृसिंहमिश्रितप्रणवो नाभ्यां न्यसनीय इत्याचक्षते; तदपि सांप्रदायिकत्वान्न विरुद्धम् ।तस्मिन्नपि पक्षे नारसिंहमिति तद्धितात् एकाक्षरो नृसिंहमन्त्रः प्रणवमिश्रितो द्वाविंशन्नृसिंहव्यूहं विहाय यावत्प्राकरणिकं मूलनृसिंहव्यूहगतमुपास्यं प्रतीयत एव ।ततश्च एतद्विद्याङ्गमेकाक्षरो नृसिंहमन्त्रो यथोक्तोपास्याभिधायकत्वात् तस्य केवलः प्रणवेन विकल्पः एकाक्षरनृसिंहमन्त्रस्य प्रणवस्तु नियत एवेति तत्त्वार्थः ।अत ऊर्ध्वं तत्तन्मन्त्रन्यासे तत्तच्चक्रेषु पत्रग्रहणम् अरतदन्तरालपत्रान्तरालव्यावृत्त्यर्थं द्रष्टव्यम् ।षट्सु पत्रेषु सुदर्शनं भवति ।ऐशानपत्रमारभ्य षडक्षरः सुदर्शनो मन्त्रो न्यसनीय इत्यर्थः ।एवमुत्तरेषु पत्रेषु योज्यम् ।अष्टसु पत्रेष्वष्टाक्षरं नारायणं भवति ।प्रणवान्तर्भावेनाष्टाक्षरतेति केचित् ।तद्वदेव द्वादशपत्रेषु द्वादशाक्षरं वासुदेवं भवतीति ।अत्रापि द्वादशाक्षरता पूर्ववत् ।षोडशपत्रेषु मातृकामन्त्रवर्णस्य आद्या वर्णमातृकाद्याः सबिन्दुका बिन्दुसहिताः षोडश स्वरा भवन्ति ।द्वात्रिंशत्सु पत्रेषु द्वात्रिंशदक्षरं सामाभिव्यक्तं मन्त्रराजमानुष्टुभं भवति ।मूलमन्त्रस्यैव एकैकमक्षरम् ।
In plain words
The word 'that' fixes exactly which wheel is meant — the wheel of thirty-two spokes, the wheel of thirty-two petals — and the word 'precisely' locks the identification down. By the rule that the first name sets the pattern, the terms starting with 'Sudarśana' show that the four wheels above are all, in truth, forms of one Great Wheel, the Mahācakra. It earns that name because the terms sit in grammatical apposition — they are naming one and the same thing. At its center — at the center of the Great Wheel — sit two navels. Since some navels are ring-shaped and lie at ground level, the text says 'in the middle, by the two navels' precisely to rule those other navels out. It is called tāraka, the crossing-syllable, because it carries a person across saṃsāra — and that tāraka is the syllable Om. The single syllable that is Nārasiṃha is called akṣara because it possesses that crossing power, or because this very form is the good of the whole world — a point already made when the word 'nṛsiṃha' was explained, and recognized again here in the word 'akṣara'. In the same way, the derived word 'nārasiṃham' conveys everything worth worshipping, beginning with the Sāma. But once everything worshippable has been named, the text narrows to a single object of worship — the array called the root Nṛsiṃha — by adding: 'possessing the one syllable'. Having said again that the syllable which is Nārasiṃha is the object of worship, and that it becomes one, and that this is the syllable, the sense is: worship is prescribed by way of its seat at the central navel of the Great Wheel, linked to the Ocean of Milk. Some hold that because the text specifically calls Nārasiṃha 'one-syllabled', it is the one-syllable Nṛsiṃha mantra fused with Om that should be placed at the navel — and since that reading, too, comes down through a genuine lineage, it is not wrong. Even on that reading, the derived word 'nārasiṃham' still points — once the twenty-two-fold Nṛsiṃha array is set aside — to the very object of worship belonging to the root array that this context concerns. So the one-syllable Nṛsiṃha mantra, being a limb of this meditation and naming the object of worship already described, has room for choice only with Om: with the plain one-syllable Nṛsiṃha mantra, Om is optional; with this mantra, Om is fixed. That is the real point. From here on, wherever a mantra is placed on a wheel, the word 'petal' should be read as ruling out the empty space between spokes and between petals — the syllables sit on the petals themselves. On six petals sits Sudarśana. Starting from the north-east petal, its six syllables are placed round the wheel — that is the meaning, and the same method carries through the remaining petals. On eight petals sits the eight-syllabled Nārāyaṇa (some count Om as part of those eight). The same way again: on twelve petals sits the twelve-syllabled Vāsudeva, its count explained exactly as before. On sixteen petals sit the sixteen vowels of the alphabet, starting from the first letter, each carrying its bindu. And on thirty-two petals sits the mantra-rāja itself, the anuṣṭubh drawn out by the Sāma, thirty-two syllables — one single syllable of the root mantra on each petal.
Close to the Sanskrit
By the word 'tat', having ascertained precisely that same wheel — the wheel with thirty-two spokes, the wheel with thirty-two petals — by the word 'eva', [the text] shows, by the maxim that what comes first governs, through words beginning with 'Sudarśana', that even the upper set of four wheels is of the nature of the Mahācakra. And [it is called] 'Mahācakra' because of grammatical co-reference. In the middle of it, in the middle of the Mahācakra, by the two central navels — for the navels that are ring-shaped and situated at ground level, in order to exclude those, it was said 'in the middle, by the two navels'. It is called 'tāraka' because it ferries one across saṃsāra; the tāraka is the syllable praṇava. The syllable which is Nārasiṃha, of a single syllable, 'possessing that' — thus it is 'akṣara'; or, this form is the world's welfare, hence 'akṣara' — this was explained at the point of expounding the word 'nṛsiṃha'; that is recognized again from the word 'akṣara'. Likewise, from the taddhita word 'nārasiṃham', everything to be worshipped, beginning with the Sāma, is conveyed. Then, everything having been understood as an object of worship, in order to state that there is one single object of worship called the array of the root Nṛsiṃha, [the text] further specifies — 'possessing one syllable'. Having restated 'the syllable which is Nārasiṃha is the object of worship', and adding 'that becomes one, and that is the syllable' — the meaning is that worship is enjoined by its being situated at the central navel of the Mahācakra, through its connection with the Ocean of Milk. On this, some say that, because of the use of the qualifying phrase 'Nārasiṃha is one-syllabled', the one-syllable Nṛsiṃha mixed with the praṇava should be installed at the navel; that too, being from a valid tradition, is not contradictory. Even on that view, from the taddhita word 'nārasiṃham', the one-syllable Nṛsiṃha-mantra mixed with the praṇava, setting aside the twenty-two-fold Nṛsiṃha array, is indeed still understood to refer to the object of worship belonging to the root Nṛsiṃha array relevant to this context. And therefore, since the one-syllable Nṛsiṃha-mantra, being a limb of this vidyā, denotes the object of worship as stated, for it there is optionality only with the praṇava; but for this mantra the praṇava is indeed fixed — such is the true purport. From this point onward, in the placement of each mantra on each wheel, the mention of 'petal' should be understood as excluding the gaps between spokes and the gaps between petals. On six petals occurs Sudarśana. Starting from the north-east petal, the six-syllabled Sudarśana mantra is to be installed — that is the meaning. In the same way it is to be applied on the remaining petals. On eight petals occurs the eight-syllabled Nārāyaṇa. Some say the eight-syllable count is by inclusion of the praṇava. In just the same way, on twelve petals occurs the twelve-syllabled Vāsudeva; here too the twelve-syllable count is as before. On sixteen petals occur the sixteen vowels, beginning with the first letter of the mātṛkā syllabary, accompanied by the bindu. On thirty-two petals occurs the thirty-two-syllabled mantra-rāja, the anuṣṭubh manifested by the Sāma. One syllable each of the root mantra itself.