Bhashya
अथ इदानीमक्षरं स्तौति, उपास्यत्वात् , प्ररोचनार्थम् , कथम् ? तेन अक्षरेण प्रकृतेन इयम् ऋग्वेदादिलक्षणा त्रयीविद्या, त्रयीविद्याविहितं कर्मेत्यर्थ - न हि त्रयीविद्यैव-आश्रावणादिभिर्वर्तते ।कर्म तु तथा प्रवर्तत इति प्रसिद्धम् , कथम् ? ओमित्याश्रावयति ओमिति शंसति ओमित्युद्गायति , लिङ्गाच्च सोमयाग इति गम्यते ।तच्च कर्म एतस्यैव अक्षरस्य अपचित्यै पूजार्थम् , परमात्मप्रतीकं हि तत् , तदपचिति परमात्मन एव स्यात् , ' स्वकर्मणा तमभ्यर्च्य सिद्धिं विन्दति मानव ' इति स्मृते ।किंच, एतस्यैवाक्षरस्य महिम्ना महत्त्वेन ऋत्विग्यजमानादिप्राणैरित्यर्थ , तथा एतस्यैवाक्षरस्य रसेन व्रीहियवादिरसनिर्वृत्तेन हविषेत्यर्थ ,यागहोमादि अक्षरेण क्रियते, तच्च आदित्यमुपतिष्ठते ,ततो वृष्ट्यादिक्रमेण प्राणोऽन्न च जायते, प्राणैरन्नेन चयज्ञस्तायते, अत उच्यते—अक्षरस्य महिम्ना रसेन इति ॥
In plain words
Now the text praises the imperishable syllable to inspire devotion, as it is worthy of meditation. How? Through this syllable operates the threefold Vedic lore—meaning the rituals enjoined by it. Ritual action does not exist independently of these invocations; rather, it proceeds precisely as 'Om, he calls; Om, he recites; Om, he chants,' indicating the Soma sacrifice. This ritual is performed solely to honor this imperishable syllable, which is a symbol of the Supreme Self, for honoring it is honoring the Supreme Self itself, as the smriti affirms: 'A person attains perfection by worshipping Him through his own duty.' Furthermore, 'by the majesty of the syllable' refers to the vital energies of the priests and sacrificer, and 'by its essence' refers to the oblations derived from grains like rice and barley. All sacrificial actions are performed using this syllable; these reach the sun, from which rain and subsequent life arise, sustaining the entire cosmic sacrifice through breath and food. Hence it is said: 'through the majesty and essence of the imperishable.'
Close to the Sanskrit
Now he praises the imperishable syllable because it is fit for worship, to inspire interest. How? By that imperishable syllable this threefold knowledge consisting of the Rigveda and others operates—meaning the ritual prescribed by the threefold knowledge. For threefold knowledge does not operate merely through invocations; rather, sacrificial action operates thus, as is well known. How? With 'Om' he gives the call, with 'Om' he recites, with 'Om' he chants the Udgitha; and from the linguistic indicator it is understood to be the Soma sacrifice. And that action is for the worship of this very imperishable syllable, for it is a symbol of the Supreme Self, and worship of it is directed to the Supreme Self alone, as supported by the smriti: 'Having worshipped him with one's duty, a mortal attains perfection.' Furthermore, 'by the majesty of this very imperishable syllable' means through the vital energies of the priests and sacrificer, and 'by the essence of this very imperishable syllable' means through the oblation derived from grain-essence such as rice and barley. Sacrifice and other actions are performed with the syllable, and that reaches toward the sun; from there, through the sequential order of rain and so forth, breath and food are produced, and through breaths and food the sacrifice is sustained. Therefore it is said: 'through the majesty and essence of the imperishable.'