Iswara Gita is an old poem available within Kurma Puranam.
This poem was appreciated by Bhagavan Ramana. The poem
is in the form of Siva-Uma conversation, as Guru Gita. This
is full of advaita jnana. I once posted about this. There
is a Ramanasramam publication of Iswara Gita, Tamil poems
by Tattvaraya Swamigal, the author of Tamil Kaivalya Navaneetam. This book is now out of print.
Atma is permanent and real, as Truth. Hence rishis call the
Atma as Truth. This is Brahman. All individual jivas, which
are nothing but bundles of egos and thoughts and which is the
product of Maya, is Avidya, unreal and impermanent. This Maya
again inseparable from Brahman. This is as old as Brahman,
and acts according to the will of Brahman, of course, depending
on individual jivas' karmas. Rishis like Sanaka transcended this
As smoke, dirt, and dust pervade the Space, but Space is
unaffected by these, the Atma within is unaffected by
indriyas (sense organs) and antakharana (mind, ego, intellect,
Upon attainement of Atma Jnana, the individuals consider
this universe as Brahman, and Jnana Swarupa. They do not
see anything other than Brahman. Only when Atma Jnana
is not attained, the individuals consider the universe as real
and is different from God and are tossed by good and bad,
pains and pleasures.
Siva further said to Uma: When a person constantly contemplate the Light in his Heart, he never suffers from pains and pleasures,
and his ego never rises its hood.* He is a Jivan Mukta and is
ever lives in Light.
* See Sad Darsanam, Verse 27.
Realizing that all elements are within him, and all elements
are both inside and outside the Brahman, he is ever in
Brahma Swarupam. He never sees anything wrong or sinful
and is ever without anything wrong or sinful.