Bhashya
किं वेत्थ, देवलोकपितृलोकप्रतिपत्तिसाधनं किं वेत्थेत्यर्थः ।अप्यत्र अस्यार्थस्य प्रकाशकम् ऋषेः मन्त्रस्य वचः वाक्यम् नः श्रुतमस्ति, मन्त्रोऽपि अस्यार्थस्य प्रकाशको विद्यत इत्यर्थः ।कोऽसौ मन्त्र इत्युच्यते— द्वे सृती द्वौ मार्गावश्रुण्वं श्रुतवानस्मि ; तयोः एका पितृणां प्रापिका पितृलोकसंबद्धा, तया सृत्या पितृलोकं प्राप्नोतीत्यर्थः ; अहमश्रुणवमिति व्यवहितेन संबन्धः ; देवानाम् उत अपि देवानां संबन्धिनी अन्या, देवान्प्रापयति सा ।के पुनः उभाभ्यां सृतिभ्यां पितृन् देवांश्च गच्छन्तीत्युच्यते— उत अपि मर्त्यानां मनुष्याणां संबन्धिन्यौ ; मनुष्या एव हि सृतिभ्यां गच्छन्तीत्यर्थः ।ताभ्यां सृतिभ्याम् इदं विश्वं समस्तम् एजत् गच्छन् समेति संगच्छते ।ते च द्वे सृती यदन्तरा ययोरन्तरा यदन्तरा, पितरं मातरं च, मातापित्रोः अन्तरा मध्ये इत्यर्थः ।कौ तौ मातापितरौ ? द्यावापृथिव्यौ अण्डकपाले ; ‘इयं वै माता असौ पिता’ इति हि व्याख्यातं ब्राह्मणेन ।अण्डकपालयोर्मध्ये संसारविषये एव एते सृती, न आत्यन्तिकामृतत्वगमनाय ।इतर आह— न अहम् अतः अस्मात् प्रश्नसमुदायात् एकंचन एकमपि प्रश्नम्, न वेद, नाहं वेदेति होवाच श्वेतकेतुः ॥
In plain words
'Do you know' means: do you know the means of reaching the world of the gods and the world of the ancestors? And on top of that, we've actually heard a seer's own words, a verse, that sheds light on this very question — there's a mantra for it too. Which mantra? This one: 'Two roads, two paths — I have heard of them, I have truly heard.' One of the two leads to the fathers, tied to their world; by that road one reaches the world of the fathers — the phrase 'I have heard' governs this, even with other words placed in between. The other road is tied to the gods, and leads there. But who actually travels these two roads to the fathers and the gods? The answer: mortals, human beings. Only humans travel by these two roads. And by those two roads, this entire restless universe moves and comes together. Those two roads run, as the verse says, 'between' something — between what? Between the father and the mother. And who are this father and mother? Heaven and earth, the two halves of the cosmic egg. The old ritual text itself explains it: 'this is the mother, that is the father.' Between the two halves of that cosmic egg, these two roads exist purely within the world of birth and rebirth — they don't lead anywhere near final deathlessness. The boy answered: 'I don't know a single one of all these questions, not one.' 'I don't know,' said Śvetaketu.
Close to the Sanskrit
'Do you know' — the sense is, 'do you know the means of attaining the world of the gods and the world of the fathers?' Moreover, here too, a saying of a sage — a mantra's word, a statement — has been heard by us, that illuminates this meaning; the sense is, a mantra too exists that illuminates this meaning. 'Which is that mantra?' it is asked — 'Two courses, two paths, I have heard; I have heard them.' Of those two, one is that which leads to the fathers, connected with the world of the fathers; the sense is, by that course one attains the world of the fathers; the construction is with 'I have heard,' with words intervening. 'Of the gods' — or also, the other one, connected with the gods; that one leads to the gods. But who, by both courses, go to the fathers and the gods? — it is said: 'of mortals' — or also, connected with human beings; the sense is, it is humans alone who go by the two courses. By those two courses, this whole moving universe converges, comes together. And those two courses, 'which lies in between' — between which two it lies in between — the father and the mother; the sense is, between the mother and father, in the middle. Who are that mother and father? — heaven and earth, the two halves of the cosmic egg; for it has been explained by the Brāhmaṇa, 'this indeed is the mother, that is the father.' Between the two halves of the cosmic egg, these two courses exist only within the domain of transmigration, not for going to absolute deathlessness. The other one, Śvetaketu, said — 'I do not know even one question out of this collection of questions, I do not know' — 'I do not know,' said Śvetaketu.