Viveka Chudamani Slokas 361-363 :

Elaborating on realizing Supreme Self in Nirvikalpa samadhi, Guru says that Supreme Self is very subtle ( अति सूक्ष्मं). It requires subtle mind to grasp the Supreme Self. It is not possible for the one with focus on gross body (स्थूल शरीरं) and other non-self ( अनात्म) entities like Ahamkara (अहंकार), to be able to grasp the subtle Supreme Self. To achieve that transformation of mind from gross thinking, to a subtle mind which is able to grasp Supreme self, the mind must be purified. The Purification is by a process of  removing the impurities of the mind, namely Rajo, Tamo and Satva Gunas.  How does one accomplish that. Guru immediately comes up with an apt example of Gold. Impurities of the Gold are removed by putting it through a fire. Just like Gold is being purified by going through the process of fire, the Mind too gets purified by a process of continuous meditation. This is what we hear in the next three Slokas.

Sloka 361

अतीव सूक्ष्मं परमात्व तत्त्वं
न स्थूल दृष्ट्या प्रतिपत्तु मर्हति।
समाधिनात्यन्त सुसूक्ष्मवृत्या
ज्ञातव्यमार्यैः अति शुद्ध बुद्धिः॥

1 अतीव सूक्ष्मं परं आत्म तत्त्वम् -
Extremely subtle is the nature of Supreme Self;


2 न स्थूल दृष्ट्या प्रतिपत्तु मर्हति-
Not by the tendency of the gross body is it possible to be known;

Supreme self is attribute-less, formless and is subtle. It is beyond the five sheaths. With the tendency of non-Self, highlighted by the outgoing nature of the mind, it is not possible to grasp the subtle Supreme Self.  The core of Guru's teaching in Viveka chudamani is that to realize Self the non Self has to be destroyed.

If it is not possible for the gross body's tendencies to know the Supreme self , who can realize the Supreme self ? That question is answered by Guru.

4 ज्ञातव्यं आर्यैः अति शुद्ध बुद्धिः-
   अति शुद्ध बुद्धिः आर्यैः ज्ञातव्यं -
   It is knowable by the noble ones with pure intellect;

How will they know?

3 समाधिना अत्यन्त सुसूक्ष्मवृत्या -
  अत्यंत सुसूक्ष्मवृत्या समाधिना-
 through Samadhi with extremely pure intellect;

The noble ones with pure intellect know (realize) the Supreme self, with extremely pure intellect  through Samadhi. Here Noble ones refers to the Seeker.

So the Samadhi to know the Supreme Self is attained by extremely pure intellect.
 

Sloka summary 361:

Extremely subtle is the nature of Supreme self; Not by the tendency of the gross body is it possible to be known;It is knowable by the noble ones with pure intellect through Samadhi with extremely pure intellect

The Supreme Self is very subtle. Subtle can be approached through Subtle only, and not by the gross is the first point. It can be approached only through pure mind. How do we attain purity of mind ? Guru says, much like Gold attaining purity by  getting rid of impurities , the mind also can attain purity by getting rid of minds impurities. We hear that in the next Sloka.

Sloka 362

यथा सुवर्णं पुटपाक शोधितम्
त्यक्त्वामलम् स्वात्म गुणं समृच्छति।
तदा मनः सत्त्वरजः  तमोमलम्
ध्यानेन संत्यज्य समेति तत्त्वम्॥

1 यथा सुवर्णं पुटपाक शोधितम् -
just as gold put through fire;

2 त्यक्त्वा अमलम् स्वात्म गुणं समृच्छति।
gives up its impurities and regains its brilliance:

3 तदा मनः सत्त्वरजः  तमोमलम्-
so also impurities of the mind namely Rajo, Tamo and Sttva
 
4 ध्यानेन संत्यज्य समेति तत्त्वम्-
(are) shed through meditation and reality is attained.

Just as gold sheds its impurities when put through fire, so also minds impurities Sattav, Rajo, Tamas are shed through the process of meditation, reality is attained much like gold attaining its brilliance.

Sloka summary 362 :

Just as gold sheds its impurities when put through fire, so also minds impurities Sattva, Rajo, Tamas are shed through the process of meditation, reality is attained much like gold attaining its brilliance.

In this Sloka Sloka also is seen as an impurity. In a Seekers search for Self, Sattav Guna plays a great role in destroying Rajo and Tamo gunas.  gita says - निर्द्वंदो नित्य सत्वस्थो भव - be free of dualities and stay in Sattva ( destroy the Tamo and Rajo Gunas).  Then having been thus used to destroy all other impurities, to reach the final stage it is said - "येन त्यजसि तत् त्यज"; That by which you have destroyed other impurities , destroy that also. So even Sattva is to be given up. Again in Gita Krishna tells Arjuna -  "निस्त्रैगुण्यो भव" - be free of all the three Gunas.  That is also what Guru says here.

So meditation is the fire to destroy the three Gunas. Guru elaborates.

Sloka 363

निरन्तराभ्यास वशात् तदित्थम्
पक्वं मनोब्रह्मणि लीयते यदा।
तदा समाधिः सविकल्पवर्जितः
स्वतो ऽद्वयानन्द रसानुभावकः॥

1 निरन्तराभ्यास वशात् तद् इत्थम् -
तद् इत्थम् निरन्तराभ्यास वशात् -
as result of constant practice, 

2 पक्वं मनोब्रह्मणि लीयते यदा-
when purified mind merges in Brahman;

3 तदा  समाधिः सविकल्पवर्जितः
  then सकल्प स्थिति become निर्विकल्प) Samadhi दि

4 स्वतो ऽद्वयानन्द रसानुभावकः-
   स्वतः अद्वयानन्द रसानु भावकः -
by itself the essence of Bliss without a second is experienced;

As a result of constant practice the purified mind merges in Brahman. Then Nirvikalpa samadhi is attained , in that state the essence of Bliss without a second is experienced by itself.

Sloka summary 363:

As result of constant practice, when purified mind merges in Brahman,  then सकल्प samadhi becomes निर्विकल्प Samadhi, the essence of Bliss without a second is experienced by itself.

॥ओं तत् सत्॥

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