Isha Upanishad says: Tad doore tad vantike (“it is far yet near”). In other words it is everywhere. What is this “it”? Hindu scriptures call it the Brahman or the IMPERSONAL ABSOLUTE which is beyond time, space and causation. Brahman is birthless, deathless and decayless and is everywhere. When a Hindu says God he is loosely calling the Brahman as God
[Isha Upanishad is one of the shortest of Upanishads consisting of 18 verses]
Problem with Man is he cannot see Brahman unless he realises it. To realise Brahman one needs to be a Jivanmukta or come out from the clutches of deadly senses which incite sensual pleasures. For Ignorant man who only sees the world through the five senses and the five perishable elements that make up the physical forms he has no chance of seeing or understanding the Brahman which is akin to seeing atoms with naked eye.
Bound by the sense-generated physical forms Man sees only the mirage of God or Brahman which is far from reality. This mirage is called Maya. Man is born under the influence of senses and is always in search of sensual pleasures. He is never tired of running after pleasures that he perceives with his senses be it gold, women, land, name, fame, beauty etc. His ego blinds him as he takes the wrong path and keeps pursuing it longing for the objects dear to his senses. He is infatuated by love and deluded by attachments to objects of indulgence. He persists in his delusion like a thirsty traveller running towards a mirage in a desert. His ego forces him to think he is on right track like the deluded traveller who thinks he is close to water that he believes exists in the oasis.
Such being the case escape from the clutches of senses is verily impossible. That is why our rishis and munis talked of killing the senses by knowledge and detachment but to do that calls for rigorous self-disciplined regimen. For a man who is free from desires indeed is free from sense slavery for he has no reason to be born again. For Jivanmuktas or who have understood the reality of the objects of the world it is just as useless as a mirage of water in the desert for an experienced traveller. The reality is about the Sun not about its rays falling on the sand creating the mirage.
There is a Jain sloka “yathaivatma akaramabhutam avalambate ….” Meaning an individual grasps only a form of a non-physical (abstract) which he constructs in his own way. Such forms differs from person to person, say from Muslim to a Christian or a Hindu. This is what then gets elaborated with changing perception and experience (of people making God in their own image).
Bible has several definition of God: God is love, light, spirit, a consuming fire. Yet it does not give any definition close to describing Him. It does offer a look at Him in four ways: God is spirit – His nature is not flesh and blood. Light – no darkness in Him; Love; and a consuming fire. These four descriptions are closest it comes in the realm of God.
In Islamic concept god is one almighty God, Allah. Allah is source of all good and evil. Nothing happens without Allah’s will. He is a strict judge and is merciful depending on the the good works and religious devotion shown by the practitioner. Otherwise there is unremitting Hell to be suffered. All Muslims must accept themselves to be servant of Allah without question.
Hinduism is different and is beyond mere physical constructs of God as it is often mistaken by aam admis and co-religionists. It is all about understanding the ultimate Oneness (Brahman) that pervades in all the known and unknown universes. Creating replicas of gods and goddesses is not to negate the Brahman but in trying to understand it. Can anyone think of Infinity without using scale models of Finity in his approach? Only saints and Jivanmuktas can resort to nirakaar puja or worship of the infinite. Ordinary man needs some sort of manifestation of gods and goddesses idols, temples, gurus, rivers, animals, etc.
Greatness of Hinduism is it gives the practitioner the FREE WILL to correct himself from what is clearly morally wrong and to raise the level of his spiritual self. (In Islam this is missing. Everything is pre-destined and a faithful has to suffer without recourse to exercising his own free will that can change his destiny). Hindus base their emancipation of bettering their lives from what they perceive was a sinful life of the past which was the cause strong enough to make them to be born again.
Therefore goal of every Hindu has to be to free oneself from the law of karma that creates repeated and unwanted cycles of births and deaths. Only the soul matters which it really should if only to regain its purity lost after getting enmeshed in the quick sand of attachments born out of senses which in turn inviting the law of Karma into play. ONLY THE ABSENCE OF LIGHT CREATES DARKNESS. LIGHT DOES NOT EXIST WHERE DARKNESS IS MADE TO PREVAIL.