Verse 8.8.4

तौ हान्वीक्ष्य प्रजापतिरुवाचानुपलभ्यात्मानमननुविद्य व्रजतो यतर एतदुपनिषदो भविष्यन्ति देवा वासुरा वा ते पराभविष्यन्तीति स ह शान्तहृदय एव विरोचनोऽसुराञ्जगाम तेभ्यो हैतामुपनिषदं प्रोवाचात्मैवेह महय्य आत्मा परिचर्य आत्मानमेवेह महयन्नात्मानं परिचरन्नुभौ लोकाववाप्नोतीमं चामुं चेति ॥ ८.८.४ ॥

tau hānvīkṣya prajāpatiruvācānupalabhyātmānamananuvidya vrajato yatara etadupaniṣado bhaviṣyanti devā vāsurā vā te parābhaviṣyantīti sa ha śāntahṛdaya eva virocano'surāñjagāma tebhyo haitāmupaniṣadaṃ provācātmaiveha mahayya ātmā paricarya ātmānameveha mahayannātmānaṃ paricarannubhau lokāvavāpnotīmaṃ cāmuṃ ceti || 8.8.4 ||

4. Seeing them leave, Prajāpati said to himself: ‘They are going without realizing or knowing anything about the Self. Anyone among them, whether a god or a demon, who will understand the teaching this way [thinking the body to be the Self] will be lost.’ Virocana, the king of the demons, went back to the demons happy in mind and explained to them the upaniṣad:

Word-for-word explanation:

Tau ha anu-īkṣya, having observed them; prajāpatiḥ uvāca, Prajāpati said; anupalabhya ātmānam, without realizing the Self; ananuvidya, without knowing; vrajatah, they have left; yatare, whoever among these two [gods or demons]; etat upaniṣadaḥ bhaviṣyanti, will understand this teaching this way; devāḥ vā asurāḥ vā, whether gods or demons; te parābhaviṣyanti iti, they will be destroyed; saḥ ha virocanaḥ, that Virocana; śāntahṛdayaḥ eva, with a happy mind; asurān jagāma, went to the demons; tebhyaḥ, to them; etām upaniṣadam ha provāca, explained the meaning of this upaniṣad; ātmā eva ha iha mahayyaḥ, the body is an object of worship in this world; ātmā paricaryaḥ, the body should be well taken care of; ātmānam eva iha mahayan, by treating the body with due respect in this world; ātmānam paricaran, by taking good care of it; ubhau lokau, both worlds; imam ca amum ca, this and the other; āpnoti iti, one attains.

Commentary:

‘The body is the Self, and in this world it should be worshipped and taken care of. If the body is worshipped and well taken care of in this world, one attains both this world and the next.’

Prajāpati deplored the fact that they had left without asking for clarification. He was their teacher and well-wisher, and he was also their grandfather. He said: ‘Poor children, they have gone away without knowing anything. They should have asked me, “When the body changes, does that mean the Self also changes?” But they did not ask any questions. Because they do not understand, they will fall away from the right path.’

Virocana went back to the demons and said: ‘I have got the answer. The body is the Self.’ Nourish this body, and look after it; eat, drink, and be merry; enjoy yourselves—this is the aim of life for a demon, that is, for a materialist. That which is gross, which can be perceived by the sense organs, that is the reality. And that which cannot be perceived is not real. This is the doctrine that Virocana preached.

The Upaniṣad uses the word upaniṣad to refer to what Virocana taught the demons, but it uses the word ironically. The word upaniṣad means niḥśeṣa—that is to say, it ‘totally destroys’ your ignorance. An Upaniṣad is supposed to give you Self-knowledge. But Virocana took the teaching to mean that the body was the Self. He thought that by worshipping and taking care of the body one would gain not only this world, but the other world also.