Verses 1.6 to 1.11
In verse 5, it has been said that knowledge is desirable as it is the only means of liberation. It will be explained later that as action is not incompatible with ignorance, it does not destroy ignorance. Instead, action perpetuates ignorance and impurities like desire and aversion remain. Knowledge alone destroys ignorance. Therefore, Upanishad teaches knowledge and does not teach action.
Purva paksha (PP) objects to the view that action is not necessary. There are three reasons. Actions, e.g., rites and rituals ordained by scriptures must be performed. If they are not performed, it will incur sin. Furthermore, performance of obligatory duties has a supportive role to pursuit of knowledge. Verse 2, Isa Upanishad says that one should perform action till the life lasts. As such, action and knowledge should be practiced together. It is called samuchayavAd: combination of action and knowledge.
PP anticipates a possible counter from siddhAnta. Knowledge does not depend on anything including action to produce liberation. PP cites Agnishotma ritual to refute it. Though its performance is sure to yield results (pleasures in higher worlds), it depends on other things, e.g., chanting of Vedic hymns. The author (sidhhAnta) is firm that Knowledge and action are incompatible and cannot go hand in hand.
Verses 1.12 to 1.24
It seems that during the time of ShankarAchArya, there was significant following of samuchayavAd. Hence, he vehemently opposes it on the basis of scriptures and reason.
1 Action depends on the performer who is desirous of results of action. He may act, may nor act or act differently. Action is purusa-tantra. The knowledge depends on the object of knowledge. A reader of newspaper has no control over its contents. Knowledge is vastu-tantra.
2 According to Sruti, Self is the left over after completion of the process of not this, not this. Self is attribute- free consciousness. It is changeless and cannot be a doer. On the other hand, an ignorant person identifies himself (I) with mind and body and is the doer. Action is accompanied with ego, whereas it is absent in man of knowledge. Self-knowledge destroys the idea of doer-ship just like right knowledge destroys the idea of water in mirage in a desert. Therefore, it is impossible for a Self-realized person to have knowledge and also perform action.
Note: BG 18.17 says that even if a Self-realized person kills many persons, killing is not attributed to him. The message is that even though a Self-realized person seemingly engages in action, the fact is that he is not a doer.
3 It is well known that ignorance is beginningless. Once it is destroyed by knowledge, it cannot arise again. It is neither in Self nor in non-Self. Once ignorance is destroyed, idea of doer-ship is removed. As such action and knowledge cannot co-exist.
4 Vedic injunctions are valid till a performer identifies himself with mind and body. Once the identification is destroyed by knowledge, Vedic injunctions lose validity. Consequently, there is no question of incurring sin.
5 Efficacy of Agnishotma, like agriculture, depends on subsidiary actions other than itself. It is not so in the case of knowledge. Hence the example of Agnishotma is not applicable here.
6 Br Up 4.5.15 says that knowledge alone, independent of action gives liberation. Therefore, action including mental ones should be renounced by an aspirer of liberation.
Note 1 The author has established that Self-knowledge and action do not exist simultaneously. A jnAni does not do action because he knows that action is done by non-Self, i.e., mind and body. There may be a doubt regarding a seeker who aspires to be a jnAni but is not yet a jnAni? The author does not talk about a seeker. It can be reasonably inferred that a seeker engages in action while pursuing knowledge. However, his actions are predominantly sAttvic: karma yoga and upAsanA yoga.
Note 2 In Naiskramasiddhi, SuresvarAchArya contrasts the verse 2 of Isopanishad with the verse 1. Verse 1 is addressed to a seeker of knowledge who aspires for liberation. The lifestyle is focused on acquiring knowledge and action is minimal. It is nivritti mArga. Verse 2 is addressed to those who are not inclined or not prepared to pursue knowledge. Such a person is advised to perform action for hundred years, i.e., till the end of life. It is called pravritti mArga. If actions are dhArmic, they purify the mind, a necessary qualification for pursuing knowledge.
1.25
It is rephrasing of the verse 5. Teaching of Upanishads is begun to impart Brahm-knowledge which removes ignorance and thereby brings the end the samsAra of transmigratory existence.
1.26
Upanishad is derived from the root word ‘shad’ which is prefixed by ‘upa’ and ‘ni’. Shad has three meanings: to loosen, to move, and to destroy. ‘Upa’ means near and ‘ni’ means certainly. Upanishad is meant to destroy ignorance. Once ignorance is removed, Brahman is revealed. With the knowledge of Brahman, samsAra comes to an end.
Contd Part 3