तम एव यस्यायतनं हृदयं लोको मनो ज्योतिर्यो वै तं पुरुषं विद्यात्सर्वस्यात्मनः परायणं स वै वेदिता स्यात् ।याज्ञवल्क्य वेद वा अहं तं पुरुषं सर्वस्यात्मनः परायणं यमात्थ ।य एवायं छायामयः पुरुषः स एषः ।वदैव शाकल्य तस्य का देवतेति ।मृत्युरिति होवाच ॥३,९.१४ ॥
In plain words
"He whose dwelling is darkness, whose world is the heart, whose light is the mind — he who knows that person, the highest goal of every self, would truly be a knower, Yājñavalkya." "I do know that person, the highest goal of every self, of whom thou speakest. He is the person made of shadow. Speak on, Śākalya. Which is his deity?" "Death," he said.