मनो ब्रह्मेति व्यजानात् ।मनसो ह्येवखल्विमानि भूतानि जायन्ते ।मनसाजातानि जीवन्ति ।मन प्रयन्त्यभिसवि-शन्तीति ।तद्विज्ञाय ।पुनरेव वरुण पितरमुपससार ।अधीहि भगवो ब्रह्मेति ।त५होवाच ।तपसा ब्रह्म विजिज्ञासस्व ।तपो ब्रह्मेति ।स तपोऽतप्यत ।स तप-स्तप्त्वा ॥ १ ॥
In plain words
He understood that the mind is Brahman. For from the mind alone indeed are all these beings born; once born, they live by the mind; and into the mind they dissolve and enter. Having realized this, he once again approached his father Varuna and said: 'Teach me, O revered one, about Brahman.' To him the father replied: 'Seek to know Brahman through austerity; austerity is Brahman.' He practiced austerity. And having performed that penance...
Close to the Sanskrit
He realized the mind is Brahman. For from the mind indeed verily these beings are born, by the mind born they live, to the mind they go forth and enter fully. Having known that, again indeed he approached Varuna the father: 'Teach, O venerable one, Brahman.' To him he spoke: 'Through austerity desire to know Brahman, austerity is Brahman.' He practiced austerity. Having performed austerity...