अवतीर्णस्तदाऽज्ञानात्तथैव सुखमस्मृतम् ।गर्भनिद्राव्यपगमे वपुः पश्यति भास्वरम्
In plain words
had descended — then, out of ignorance, his bliss likewise unremembered — upon the passing of the sleep of the womb he beholds a radiant body.
अवतीर्णस्तदाऽज्ञानात्तथैव सुखमस्मृतम् ।गर्भनिद्राव्यपगमे वपुः पश्यति भास्वरम्
had descended — then, out of ignorance, his bliss likewise unremembered — upon the passing of the sleep of the womb he beholds a radiant body.