Sloka 57 and 58

Hari OM,

SLOKA 57:
atadvachyaavR^ittiruupeNa vedaantairlakshyatedvayam.h .
akhaNDaanandamekaM yattatad.hbrahmetyavadhaarayet.h .. 57..

Pada artha:
Atat: not this
Vyaavrithi roopena: by the process (of negation)
Vedaantaihi: by the Vedanta philosophy
Lakshyate: indicated
Adwayam: non dual
Akhanda anandam: indivisible and blissful
Ithi: thus
Avadhaarayet: realize
Ekam: one
Yat: which
Tad Brahma: that to be Brahman

Realize that to be Brahman which is Non-dual, Indivisible, One and Blissful and which is indicated in Vedanta as the Immutable Substratum, realized after the negation of all tangible objects.

In these two slokas, Achraya is continuing the explanation of the nature of Brahman. Brahman has to be realized as that which is indicated by the process of negation in Vedanta. The Non dual and indivisible Brahman can never be known by the thoughts or by any actions as it can never be an object of cognition and is verily the subject and the illuminator of all the thoughts and actions.
Acharya is here explaining that it is that which is the very substratum for all existence.

Kaivalya Upanishad proclaims the same about Brahman as:
yatparaM brahma sarvaatmaa vishvasyaayatanaM mahat.h
suukShmaatsuukshmataraM nityaM tattvameva tvameva tat.h .. 16..

That which is the Supreme Brahman, the soul of all, the great support of the universe, subtler than the subtle, and eternal – that is thyself, and thou art That.

mayyeva sakalaM jaataM mayi sarvaM pratiShThitam.h
mayi sarvaM layaM yaati tad.hbrahmaadvayamasmyaham.h .. 19..

In me alone is everything born, in me does everything rest, and in me is everything dissolved. I am that Brahman, the second less.

The great support of all creations, the Brahman, being one without second does not admit any differences nor can undergo any changes and hence is described here as indivisible, non dual and immutable. The Upanishads indicate that the Brahman is reached by a process of negation of what is not and of assertion of what it is. i.e. by the direct method and the method of negation. This is explained in the Brihadaranyaka Upanishad 2.3.6 as “Now therefore the description (of Brahman) is: ‘Not this, not this’. Because there is no other and more appropriate description than this ‘Not this’. Now Its name: ‘The Truth of truth’. The vital force is truth, and It is the Truth of that.”

Here it is explained that Brahman is that which is realized after the process of negation. When all the objects of the world are negated as illusory, that which remains as the witness, as the substratum to all the illusions, that is to be realized as Brahman. Acharya continues to explain the swaroopa lakshana in the next sloka as:

SLOKA 58:
akhaNDaanandaruupasya tasyaanandalavaashritaaH .
brahmaadyaastaaratamyena bhavantyaanandino lavaaH .. 58..

Pada artha:
Akhanda ananda roopasya: whose nature is unbroken Bliss
Tasya: His
Ananda laya ashritaha: depending only upon a particle of Bliss
Brahma adhyaha: the creator and other deities
Taaratmyena: in proportion
Bhavanti: are
Anandinaha: enjoying the bliss
Akhilaha: all

Deities like Brahma and others taste only a particle, of the unlimited Bliss of Brahman and enjoy in proportion their share of that particle.

Acharya here is explaining the Brahman which is verily bliss by giving a relative picture. It is difficult for a limited intellect to even imagine the vastness of the unlimited bliss of reality. Hence Acharya here is explaining that the devas like the creator Brahma himself tastes only a particle of that limitless and unbroken bliss.

This limitless joy is not measured here but we are only shown here how the ethereal joy of even the Gods is but negligible compared to it. As learnt in the previous slokas also, this is the supreme bliss after attaining which there remains a desire for nothing. Shruti explains the absoluteness of Brahmananda in Brihadaranyaka upanishad. 4.3.32 as:

eshhAsya paramA gatir
eshhAsya paramA saMpad
eshho.asya paramo loka
eshho.asya parama Ananda
etasyaivA.a.anandasyAnyAni bhUtAni mAtrAmupajIvanti

This is its supreme attainment, this is its supreme glory, this is its highest world, this is its supreme bliss. On a particle of this very bliss other beings live.

Let us learn more in the next sloka.

Hari OM

With regards,
Mallika R
What you have is God's gift to you and what you do with what you have is your gift to God