Bhashya
अष्टाक्षर प्रथमः पादो भवतीत्यादि सप्रणवं सर्वं पञ्चमंभवतीत्यन्तं स्पष्टार्थम् ।ॐ हृदयेत्याद्यङ्गमन्त्राणां पञ्चानांसामाङ्गमन्त्रैरेव व्याख्यातत्वात् न पृथग्व्याख्यानापेक्षेति,हृदयेत्यादि पञ्चमेनेत्यन्तं स्पष्टार्थम् ।व्यतिषक्ता वाइमे लोकास्तस्माद्व्यतिषक्तान्यङ्गानि भवन्तीति लोकबुद्धयो-पास्यानां हृदयाद्यङ्गानां सामाभिव्यक्तमूलमन्त्रप्रति-पाद्ये नृसिंहब्रह्मव्यूहे क्षीरोदार्णवशायिनि उपविष्टे वालोकव्यतिषङ्गहेतुकाङ्गव्यतिषक्तता विधीयते ।तस्माद्व्यति-षक्तान्यङ्गानि भवन्तीत्यत्र व्यतिषक्तानि यथायोग्यतयाअन्योन्यं मिश्रितान्युपास्यानीत्यर्थः ।ततश्च अयमर्थः सं-पद्यते- पारमेश्वरं हृदयाख्यमङ्गं पारमेश्वरशिरोऽङ्गादधःप्रदे-शान्तःस्थितं हृदयप्रदेशादारभ्य उपास्यम् ।अत एव सा-माङ्गप्रणवव्याख्यानेन मूलमन्त्रहृदयाङ्गव्याख्यानावसरे पार-मेश्वरं हृदयं व्याख्यातम् ; इतरथा तद्व्याख्यानमप्रस्तुतं स्यात् ;तस्मादङ्गव्यतिषक्तताविधानादेव तद्व्याख्यानं प्रस्तुतमिति सि-द्धम् ।यत एवं हृदयाङ्गोपासनैव तदन्तर्गतत्वात् नेत्रत्र-योपासना, अत एव नेत्रत्रयाङ्गोपासना न पृथगभिहिता ।एवमुत्तरत्रापि शिखाख्यमङ्गं पारमेश्वरं शिरोऽङ्गे मूर्ध्नि चव्यतिषक्तं सामाङ्गलक्ष्मीयजुर्मन्त्रेण व्याख्यातमुपास्यम् ।शिरश्च द्वितीयमङ्गं यथोक्तहृदये व्यतिषक्तं सामाङ्गसावित्री-मन्त्रेण व्याख्यातम् ।पारमेश्वरं कवचम् यथोक्तहृदयैकदेशेनाभेरूर्ध्वं ग्रीवातोऽधः पृष्ठप्रदेशव्यापि सामाङ्गनृसिंहगाय-त्र्या व्याख्यातमुपास्यम् ।एवं पञ्चममङ्गम् अस्त्राख्यम्उत्तराधरभावेन तन्नाभिमध्यवर्ति क्षीरोदार्णवशायिपारमेश्वर-व्यूहचतुष्टयाङ्गव्यापितया व्यवस्थितं व्यतिषक्तमुपास्यमितियथायोग्यतया व्यतिषक्तशब्दस्याङ्गेषु स्थितिः ।पञ्चाङ्गन्या-सोपन्यासः न षष्ठमङ्गमिति तस्य हृदयान्तर्गतत्वात् इतिप्रागभिहितम् ।
In plain words
The line 'the first foot has eight syllables', all the way to 'the fifth, carrying Om, is everything' — that one speaks for itself. And the five limb-mantras that open 'Oṃ, to the heart…' have already been unpacked completely through their matching Sāma chants, so there is nothing left to add; that whole stretch, 'heart' through 'by the fifth', also speaks for itself. Now, 'these worlds are woven into one another, and so the limbs are woven into one another too' — the heart and the other limbs are meditated on precisely as the worlds themselves are pictured, within the great form of Narasiṃha-as-Brahman that the Sāma brings to light out of the root mantra — whether you picture him reclining on the ocean of milk or seated upon it. Because the worlds interweave, the limbs are made to interweave as well; that is the rule being laid down. 'Interlinked' does not mean vague or careless — it means each limb, in exactly the measure that suits it, is blended with the others in meditation. That is all the word is saying. And here is where it leads: the heart, as the Lord's own limb, sits in the region just below his head, and the meditation begins there, at the heart. That is exactly why, when the Sāma's version of the praṇava was being explained, the Lord's heart got explained in the very same breath — because if it hadn't, that explanation would have had nowhere to belong. The rule that binds the limbs together is precisely what makes that earlier explanation relevant, and so the point stands proven. And since that is so, meditating on the heart already carries the three eyes with it — they are folded into the heart — which is exactly why the three-eyed meditation is never given as a separate topic. In the same way, further on, the crest — the Lord's own limb — sits on the crown, woven together with the head, and it is explained and meditated on through the Sāma's Lakṣmī-Yajus verse. The head itself, the second limb, is woven together with the heart just described, and explained through the Sāma's Sāvitrī verse. The Lord's armor covers the back, from above the navel up to below the neck, occupying one part of that same heart, and it is explained and meditated on through the Sāma's Narasiṃha-Gāyatrī. And the fifth limb, the weapon, sits above and below at once, running through all four limbs of the Lord's array as he reclines at the centre, on the ocean of milk — woven into everything, and meditated on as such. That is how the word 'woven together' applies, each time in the measure that fits. Laying out these five limbs is not, somehow, a sixth limb of its own — it already belongs to the heart, as was said before.
Close to the Sanskrit
[The passage] beginning 'the first foot is of eight syllables' up to '...the fifth, together with the praṇava, is all' has a clear meaning. Since the five limb-mantras beginning 'Oṃ, to the heart...' are already explained precisely by the Sāma-limb mantras themselves, no separate explanation is called for; thus [the passage] beginning 'heart' up to '...by the fifth' has a clear meaning. [As for] 'these worlds indeed are interlinked, therefore the limbs become interlinked' — for the heart and the other limbs, which are meditated upon through the notion of the worlds, in the Narasiṃha-Brahman array made manifest by the root-mantra through the Sāma, [the Lord] reclining on the ocean of milk, or seated, the interlinking of the limbs caused by the interlinking of the worlds is enjoined. As to '...therefore the limbs become interlinked' — here 'interlinked' means: as is fitting, [the limbs] are to be meditated upon mixed with one another; that is the meaning. And so this sense results: the limb called 'heart', belonging to the Supreme Lord, situated within the region below the head-limb of the Supreme Lord, is to be meditated upon starting from the region of the heart. For this very reason, on the occasion of explaining the heart-limb of the root-mantra by means of the explanation of the praṇava of the Sāma-limb, the heart belonging to the Supreme Lord has [already] been explained; otherwise that explanation would be out of place; therefore, precisely because of the prescription of the interlinking of limbs, it is established that that explanation belongs there. Since this is so, the meditation on the heart-limb alone [suffices], because the meditation on the triad of eyes is included within it; for this very reason the meditation on the eye-triad limb has not been stated separately. In the same way, further on, the limb called 'tuft', belonging to the Supreme Lord, interlinked with the head-limb, on the crown, has been explained by the Sāma-limb's Lakṣmī-Yajus mantra and is to be meditated upon. And the head, the second limb, interlinked with the heart as stated, has been explained by the Sāma-limb's Sāvitrī mantra. The armor, belonging to the Supreme Lord, pervading the back-region above the navel and below the neck, in one part of the heart as stated, has been explained by the Sāma-limb's Narasiṃha-Gāyatrī and is to be meditated upon. Thus the fifth limb, called 'weapon', situated by pervading the four limbs of the array of the Supreme Lord reclining on the ocean of milk that lies at the middle of that navel, in respect of both the upper and lower, is to be meditated upon as interlinked — thus, as is fitting, is the usage of the word 'interlinked' among the limbs. The mention of the installation of the five limbs is not [the mention] of a sixth limb, because it is included within the heart — this has already been stated.