Bhashya
एकश्चात्मा स्वप्नबुद्धान्तयोर्महामत्स्यवदसङ्गः संचरतीति श्रुत्यन्तरे सिद्धम् ।यच्चोक्तं संप्रसादः शरीरात्समुत्थाय यस्मिन्स्त्र्यादिभिः रममाणो भवति सोऽन्यः संप्रसादादधिकरणनिर्दिष्ट उत्तमः पुरुष इति, तदप्यसत् ।चतुर्थेऽपि पर्याये 'एतं त्वेव ते' इति वचनात् ।यदि ततोऽन्योऽभिप्रेतः स्यात्, पूर्ववत् 'एतं त्वेव ते' इति न ब्रूयान्मृषा प्रजापतिः ।किंचान्यत्, तेजोबन्नादीनां स्रष्टुः स्वतः स्वविकारदेहशृङ्गे प्रवेशं दर्शयित्वा प्रविष्टाय पुनः तत्त्वमसीत्युपदेशः मृषा प्रसज्येत ।तस्मिंस्त्वं स्त्र्यादिभिः रन्ता भविष्यसीति युक्त उपदेशोऽभविष्यत् यदि संप्रसादादन्य उत्तमः पुरुषो भवेत् ।तथा भूम्नि 'अहमेव' इत्यादिश्य 'आत्मैवेदं सर्वम्' इति नोपसमहरिष्यत्, यदि भूमा जीवादन्योऽभविष्यत्, 'नान्योऽतोऽस्ति द्रष्टा' इत्यादिश्रुत्यन्तराच्च ।सर्वश्रुतिषु च परस्मिन्नात्मशब्दप्रयोगो नाभविष्यत् प्रत्यगात्मा चेत्सर्वजन्तूनां पर आत्मा न भवेत् ।तस्मादेक एव आत्मा प्रकरणी सिद्धः ॥
In plain words
That the single Self moves through the waking and dream states completely unattached, like a great fish gliding through water, is established in other sacred texts. The claim that the soul in deep sleep rises from the body, revels with companions, and is something distinct from the supreme person designated in the text is likewise false. For in the fourth section, Prajapati tells Indra 'This alone I declare to you'; if a different entity were meant, he would not repeat those exact words without falsehood. Moreover, after showing how the creator of the elements enters into the very body he produced, teaching him 'Thou art that' would be meaningless if the soul were something separate from the supreme. If a different entity were intended, the instruction would have told him he would simply enjoy worldly pleasures in that state. Similarly, in the teaching on the Infinite, after declaring 'I alone am all this,' the text would not conclude with 'All this is verily the Self' if the Infinite were separate from the individual soul, as other passages confirm by stating 'There is no other seer than this.' Across all scriptures, the term 'Self' would never be applied to the supreme if the inner self were not the true self of all beings. Therefore, it is established that the sole Atman is the ultimate subject of the teaching.
Close to the Sanskrit
And that the one Self moves about unattached like a great fish in the dream and waking states is established in another Vedic text. And what was said—that the deep-sleep soul having risen up from the body, revelling with women and others, becomes different from the deep-sleep state and is the highest person indicated by the topic—that also is untruth. Because in the fourth section also, from the statement 'This indeed I declare to thee,' if another were intended than that, Prajapati would not speak falsely 'This indeed I declare to thee' as before. Furthermore, having shown the entry of the creator of fire, water, food, and others by himself into the peak of his own modified body, the instruction subsequently given to the one who has entered—'Thou art that'—would result in being false. If the supreme person were other than the deep-sleep soul, the instruction would have been appropriate thus: 'In that state thou shalt be an enjoyer with women and others.' Similarly, in the teaching of the Infinite, having instructed 'I alone am this,' he would not have concluded with 'All this is verily the Self,' if the Infinite were other than the jīva, and also on account of other scriptural passages such as 'There is no other seer than this.' And in all scriptures the application of the term 'Self' to the supreme would not exist if the inner self were not the supreme self of all creatures. Therefore, it is established that the sole Self is the subject matter under discussion.