Athma in Reality Is Paramatma

 I would like to mention 4 MAHA VAKYAS of 4 VEDAS--

1)PRAGYANAM BRAHMAHA (CONSCIOUSNESS IS BRAHMAN)

2)AYAM ATHMA BRAHMAHA

3)AHAM BRAHMASMI

4)TATVAM ASI (THOU ART THAT).  

All the above indicates that ATHMA IS BRAHMAN WHICH IS NOT DIFFERENT FROM PARAMATHMAN.

Following is the extract from MEHER BABA'S book GOD SPEAKS which may be useful to you--

Athma in Reality Is Paramatma

In order to clarify the relationship of “atma-Paramatma” we compare Paramatma 

with an infinite ocean, a limitless ocean, and the atma as a drop in this ocean. 

The atma is never out of this limitless ocean ( Paramatma ) .The atma can never 

be out of Paramatma because Paramatma is infinite and unlimited. How can

 the atma come out of, or have a place beyond, the limitlessness of the limitless? 

Therefore the atma is in Paramatma .After establishing the primary fact that the

 atma is in Paramatma we go a step further and say that atma is Paramatma.

      How ?For example, let us imagine an unlimited ocean. Let us also imagine that

 we separate or take out one iota of ocean from the limitless expanse of this 

unlimited ocean. It follows then that this iota of ocean, while in the limitless ocean, 

before separation is ocean itself, and is not there in the shoreless ocean as an

 iota of the ocean,because every iota of ocean, when not limited by the limitations

of a drop, is unlimited ocean.

               It is only when an iota of ocean is separated from the unlimited ocean, 

or is taken out of the unlimited ocean as a drop, that this iota of ocean obtains

 its separate existence as a drop of the shoreless ocean, and that this iota of

 ocean begins to be looked upon as a drop of the unlimited ocean. In other words, 

the infinite, unlimited and limitless ocean itself is now looked upon as merely

 a drop of that infinite, unlimited and limitless ocean. And in comparison to that 

infinite, unlimited and limitless ocean this iota of ocean, or this drop of the iota

 of ocean, is most finite and most limited with infinite limitations. That is, the 

infinitely free iota finds itself infinitely bound.Similarly, the atma, which we have compared with a drop of the infinite ocean, obtains a seeming separate existence,

 though in reality it can never be out of the limitlessness of the limitless, infinite 

Paramatma which we have compared with the infinite, unlimited and limitless

 ocean.But just as the iota of ocean acquires its limitation as a drop through being in the form of a bubble on the surface of the ocean, and the bubble bestows upon

 the iota of ocean an apparently separative existence from the infinite ocean,

 likewise the atma, which is in Paramatma and is Paramatma, apparently experiences separative existence from the infinite Paramatma through the limitations of a bubble (of ignorance) with which the atma shrouds itself. No sooner

 does the bubble of ignorance burst, than the atma not only finds itself in Paramatma but experiences itself as Paramatma.Through this limitation, formed by

 the bubble of ignorance, self-created by the atma, the atma apparently inherits 

a separative existence from Paramatma. And because of this self-created 

separativeness from infinite Paramatma, the atma, which is itself infinite,unlimited

 and limitless, apparently experiences itself as most finite with infinite limitations.