Bhashya
अत्र आहुः केचित्- चतुर्णामाश्रमिणामविशेषेण स्वधर्मानुष्ठानात्पुण्यलोकता इहोक्ता ज्ञानवर्जितानाम् 'सव एते पुण्यलोका भवन्ति' इति ।नात्र परिव्राडवशेषित, परिव्राजकस्यापि ज्ञानं यमा नियमाश्च तप एवेति, तप एव द्वितीय इत्यत्र तप शब्देन परिव्राट्तापसौ गृहीतौ ।अतस्तेषामेव चतुर्णां यो ब्रह्मसंस्थः प्रणवसेवक सोऽमृतत्वमेतीति चतुर्णामधिकृतत्वाविशेषात्, ब्रह्मसंस्थत्वेऽप्रतिषेधाच्च, स्वकर्मच्छिद्रे च ब्रह्मसंस्थताया सामर्थ्योपपत्ते ।न च यववराहादिशब्दवत् ब्रह्मसंस्थशब्द परिव्राजके रूढ, ब्रह्मणि संस्थितिनिमित्तमुपादाय प्रवृत्तत्वात् ।न हि रूढिशब्दा निमित्तमुपाददते ।सर्वेषा च ब्रह्मणि स्थितिरुपपद्यते ।यत्र यत्र निमित्तमस्तिब्रह्मणि सस्थिति, तस्य तस्य निमित्तवतो वाचक सन्त ब्रह्मसस्थशब्द परिव्राडेकविषये सकोचे कारणाभावात् निरो द्धुमयुक्तम् ।न च पारिव्राज्याश्रमधर्ममात्रेणामृतत्त्वम् , ज्ञा नानर्थक्यप्रसङ्गात् ।पारिव्राज्यधर्मयुक्तमेव ज्ञानममृतत्वसाध नमिति चेत् , न, आश्रमधर्मत्वाविशेषात् ।धर्मो वा ज्ञान- विशिष्टोऽमृतत्वसाधनमित्येतदपि सर्वाश्रमधर्माणामविशिष्टम् ।न च वचनमस्ति परिव्राजकस्यैव ब्रह्मसस्थस्य मोक्ष , नान्येषाम् इति ।ज्ञानान्मोक्ष इति च सर्वोपनिषदा सिद्धा न्त ।तस्माद्य एव ब्रह्मसस्थ स्वाश्रमविहितधर्मवताम् , सोऽमृतत्वमेतीति ॥
In plain words
Some commentators argue here that the attainment of heavenly worlds is promised to all four stages of life alike, provided they perform their duties but lack direct realization. They claim the sannyasi is not excluded from this, since the sannyasi's disciplines are also a form of austerity, and 'austerity' can include both the hermit and the wanderer. Thus, they argue, whichever of the four orders becomes anchored in Brahman and contemplates Om attains immortality, since everyone is equally eligible and there is no rule forbidding anyone from abiding in the Absolute. They even suggest one can meditate on Brahman in the gaps between ritual duties. Furthermore, they claim 'established in Brahman' is not a title exclusive to the sannyasi, but a descriptive term applicable to anyone who abides in the Divine. But this cannot be. If the mere outward lifestyle of a wanderer brought liberation, spiritual wisdom would be useless. If you say wisdom only works when combined with the sannyasi lifestyle, we reply that this lifestyle is still just an outward duty. If you say duty combined with wisdom brings liberation, then this should apply to the duties of all stages of life. There is no scriptural text declaring that only a sannyasi can attain liberation. The final, unshakeable truth of all Upanishads is that liberation comes from wisdom alone. Therefore, whoever is truly established in Brahman—transcending all outward roles—attains absolute immortality.
Close to the Sanskrit
Here some say: The attainment of holy worlds is stated here for the four stage-dwellers without distinction, who perform their own duties but are devoid of knowledge, as 'all these become possessors of holy worlds.' The wanderer is not excluded here, because for the wanderer also, knowledge, restraints, and observances are austerity indeed, and by the word 'austerity' in 'austerity indeed is the second,' both the wanderer and the ascetic are taken. Therefore, among those four, whoever is established in Brahman, a worshipper of Pranava, he attains immortality, because of the equal qualification of the four and because of the lack of prohibition against being established in Brahman, and because of the feasibility of being established in Brahman in the intervals of one's own actions. And the word 'established in Brahman' is not conventionally fixed on the wanderer like the words 'yava' or 'varaha', because it is applied by taking the cause of being established in Brahman. Conventional words do not take a cause. And establishment in Brahman is possible for all. Wherever there is the cause, namely establishment in Brahman, the word 'established in Brahman' is expressive of that possessor of the cause, and it is improper to restrict it to the wanderer alone due to the absence of any reason for restriction. And immortality is not by the mere duty of the order of sannyasa, because of the consequence of the uselessness of knowledge. If it is said that knowledge accompanied by the duty of sannyasa is the means to immortality, no, because of the equal status of being an ashrama duty. Or, if duty qualified by knowledge is the means to immortality, this also is common to all ashrama duties. And there is no statement that liberation is only for the wanderer who is established in Brahman, not for others. And liberation is from knowledge, which is the established conclusion of all Upanishads. Therefore, whoever among those possessing the duties ordained for their own ashrama is established in Brahman, he attains immortality.