Listen, O disciple, O you of great wisdom. This what you have asked me is not described even in the very Vedas and is the highest subject for thought or discourse. It is called Adhyatma and is the most precious of all branches of learning and of all sacred institutes.
गुरुरुवाच शृणु शिष्य महाप्राज्ञ ब्रह्मगुह्यमिदं परम्। अध्यात्म सर्वविद्यानामागमानां च यद्वसु॥