अस्तमित आदित्ये याज्ञवल्क्य चन्द्र-मस्यस्तमिते शान्तेऽग्नौ किंज्योतिरेवायंपुरुष इति वांगेवास्य ज्योतिर्भवतीतिवाचैवायं ज्योतिषास्ते पल्ययते कर्म कु-रुते विपल्येतीति तस्माद्वै सम्राडपि यत्रस्वः पाणिर्न विनिर्ज्ञायतेऽथ यत्र वागुच्चर-त्युपैव तत्र न्येतीत्येवमेवैतद्याज्ञवल्क्य ॥
In plain words
The sun has gone down, Yājñavalkya. The moon has set too, and the fire has burned down to quiet. So what light does this man have left? Speech, comes the answer -- speech alone is his light now. By that light of speech he sits, he moves, he does his work, he comes back again. That is why, great king, even when your own hand is lost in the dark, you can still find your way: follow a voice, and you arrive right where it is. That is exactly how it is, Yājñavalkya.
Close to the Sanskrit
The sun having set, Yājñavalkya, the moon having set, the fire having become quiet, what, then, is the light of this person? [He said:] Speech alone is his light; by speech alone as his light he sits, he goes about, he does work, he returns. Therefore indeed, O sovereign, even where one's own hand cannot be discerned, yet where speech is uttered, one goes right up to that point. Even so is it, Yājñavalkya.