Is it Possible to Attain Oneness?

All religions and Holy Scriptures claim and preach that “we are one".
But yet, we see so many divisions everywhere based on skin-color, economics, profession, 
upper and lower classes, nationality, political & religious views, etc. 

Christianity preaches - We are all children of God. And God loves everyone equally.
Hindus believe: "Mujh me Ram, tujh me Ram – Sab main Ram samaya".
“There is Ram (God) Within me and there is Ram within you
 – Ram (one Almighty God) prevails in everyone”.

In the Quran, Allah says: 
"We have sent our messengers in every community in the world (to unite them)"

Guru Kabeer ji says: 
“Avval Allah noor upaayaa- qudart ke sab banday” - 
"God created everyone – all people are from His divine nature".

Sant Namdev proclaimed: 
“Sab Govind hai, sab Govind hai, Govind binu nahi koi”
All is God - All is God – There is no one other than God”.

According to Gurubani: 
सबै घट राम बोले रामा बोले - राम बिना को बोले रे”
“Sabai ghat Ram bolay, Raama bolay – Ram bina ko bolay re?”
Ram (God) speaks through every form (body) - who speaks other Than Ram (god)?
Sab mai ek reha bharpoor   - सब मंह  एक रहिआ भरपूर  
One Almighty God prevails in everyone and everything.
Sab mahin Jot - Jot hai eko  सब मंह  जोत - जोत  है एको 
There is Holy spirit in everyone and the spirit is one. 

Avtar Bani also proclaims:
             इको नूर दी उपज है सारी - इक दा सगल पसारा है 
"Iko noor di upaj hai saari – ik da sagal pasaara hai” 
“Everything is creation of the same Divine light (of God)  The one and only God prevails all around”

In fact, there are hundreds of such references in all Holy books - these are just a few quotes for example.

As we can see clearly from the above references – all religions claim oneness of whole humanity and yet we see more divisions on the grounds of Religions and faith itself. 
So, naturally a question arises in mind – “is it ever possible to attain Oneness? 
Oneness of whole humanity - and to see oneness in everything?”

Great sages and scholars of the past and the psychologists have tried to find the ways of breaking the walls and uniting the divided humanity. One good solution is to preach the concept of Oneness of God. Logically, when God; The Father is one - then all children must also be one – which makes everyone a part of one big family and creates a sense of belonging to each other. 
Being part of a harmonious and loving community helps to dissolve our barriers and limiting beliefs, and to grow and implement the feelings of Oneness. Community supports us on our own journey and allows us the opportunity to serve others. It helps us open up to new and different ideas and connect us with a sense of Oneness.
Therefore, the followers of all great saints and scholars - Prophets and messengers started their own communities – loving and harmonious - with a sense of belonging to each other. Because there was love, harmony and a sense of security by being with like-minded people around, more and more people got attracted towards such communities and joined them. But unfortunately, in this process they became disconnected from others - even from their old, original communities and slowly, more and more new communities kept forming. 
Moreover – over the period of time, such communities became much bigger and the differences started to creep in within each of these new formed communities as well. 
And eventually, the very purpose of creating or founding these communities was lost. 

So, the question still remains– “is it ever possible to attain Oneness?

Yes, but only through direct experience, when we go beyond the mind, intellect, and ego.
The fact is that we are one but we think we are separate. We have forgotten our Oneness. 
The ancient Hindu Scriptures taught the Advaita philosophy; the philosophy of Non-Duality.
                 "Ekah Brahm, Dviteeya naastay". (Rig Veda)
There is only one God - without the second. 
Furthermore, Non-duality does not mean only the Oneness of God, but oneness of the universe as well. 
When we forget this principle of Non-duality, we create an illusory world of duality, which leads to suffering. 
All disagreements, conflict, and wars are due to the mistaken belief of duality - that we are separate. 
Somewhere, I read this beautiful analogy:
"When we realize we are one, who, or what is there to fight against? On a cosmic level, two people fighting is as ridiculous as if your hands decided they didn’t like each other and started fighting".

Our both hands are not exactly the same - one is usually stronger than the other - but nonetheless, they are part of the same body. Similarly, all humans may not appear to be similar and equal, but everyone is a part of the same Divine-Nature of the Almighty.

Oneness does not mean coming together of all like-minded people - with similar ideology and goals. 
Oneness is the coming together of all opposites.

                    'Rajan Sachdeva'