सर्वधर्मान्परित्यज्य मामेकं शरणं व्रज।
अहं त्वा सर्वपापेभ्यो मोक्षयिष्यामि मा शुचः।।18.66।।
Meaning: Having renounced all actions, seek ME, the nondual, (as your) shelter. I shall liberate you from all sins. Do not grieve. [SwAmi ParmArthAnanda]
Chapter 18 is the last chapter of the BG and verse 66 is the last verse of the teaching of the BG. Therefore, it is called charam [final] sloka. Verses 67 to 78 are winding up verses. Standalone 18.66 looks ordinary. To quote SwAmi ChinmayAnanda, when the essence of teaching is packed in a few words, it may be deceptive.
18.66 has four parts. According to SwAmi ParmArthAnanda, the literal meanings of the first two quarters are controversial. Sri Krishna asks Arjuna to renounce virtuous actions too, not one or two but all whereas He Himself has incarnated to establish dharma [4.7]. Furthermore, unscrupulous people may take advantage of this verse and justify immoral actions. In later quarters, Sri Krishna asks Arjun to take refuge in Him alone. It may be taken to ignore other personal gods as Sri Krishna alone can ensure freedom from all sins. Krishna’s words cannot be faulted. Hence, we have to discard literal meaning and take recourse to suggestive meaning. No doubt, immoral actions have to be given up. The dilemma is to perform moral actions and yet ‘renounce’ them. For this, we have to recollect the teachings in earlier chapters and verses. The mind-body duo performs actions. Therefore, the way to ‘renounce’ moral actions is not to identify with mind and body. It is possible if I identify myself with a different entity. That I am a conscious being is beyond doubt. The BG teaches that the real nature of the jivA is consciousness and the mind-body is an adjunct. Thus, giving up virtuous actions, while performing them, is possible if I cognitively disassociate from mind and body and identify myself with consciousness. It is not a fantasy as my real nature is consciousness and habitual identification with mind-body is a mistake. This explains tvam (jiva-swarupa) of the mahAvAkya, tat-tvam-asi.
Sri Krishna asks Arjun to take refuge in Him. He is an avatAra of God. The God has two natures, aparA prakriti (sagun brahman) and parA prakriti (nirgun brahman) [Chapter 7]. Sagun brahman are of two types, namely, ek rupa and aneka rupa. Ek rupa is a personal god and aneka rupa is visva rupa [ Chapter 11] and nirgun brahman is pure existence that is arupa [formless]. In 18.66, nirgun brahman is referred to, i.e., ‘tat’. Advaita says that pure existence and pure consciousness are one and the same. Taking refuge in Him means removing any difference of time and space between jiva (tvam) and nirguna brahman (tat) and abiding in the mahAvAkya: I am brahman.
Taking refuge means surrender(sarnAgat). Therefore, it is a sarnAgat sloka and SarnAgat also means the identity of jivA and brahman. Sri Krishna assures that a person established in this knowledge is freed from all sins. Later, He asks (18.72) if Arjuna has listened to the spiritual instructions with a concentrated mind and if his ignorance and delusion are destroyed. Arjuna confirms (18.73) that he has gained wisdom and he is from doubts and delusion. [Primary source: Talks of SwAmi ParmArthAnanda]. Part 2 looks at 18.66 BGB
Note: The word मामेकं [mAmekam: mam+ekam] occurs in the verse. As ekam can have two meanings, ‘alone’ and ‘non-dual’, मामेकं can have two meanings: ‘me alone’ and ‘non-dual me’. Thus, literal meanings lead to confusion. On the other hand, if suggestive meaning, namely,(nirgun) brahman, is taken, there is no confusion. [Contd]