How do you define God?
Or
How do you define the absense of God?

I define God as Love.

Are you looking to get some religion Tom?

The same way I define Spiderman

Well not exactly, Spiderman is much more amusing

I define the Christian God as perfect love, Holy, omniscient, omnipotent and omnipresent.

Omnipotence means all-powerful. Monotheistic theologians regard God as having supreme power. This means God can do what he wants. It means he is not subject to physical limitations like man is. Being omnipotent, God has power over wind, water, gravity, physics, etc. God's power is infinite, or limitless.

Omniscience means all-knowing. God is all all-knowing in the sense that he is aware of the past, present, and future. Nothing takes him by surprise. His knowledge is total. He knows all that there is to know and all that can be known.

Omnipresence means all-present. This term means that God is capable of being everywhere at the same time. It means his divine presence encompasses the whole of the universe. There is no location where he does not inhabit. This should not be confused with pantheism, which suggests that God is synonymous with the universe itself; instead, omnipresence indicates that God is distinct from the universe, but inhabits the entirety of it. He is everywhere at once

God is a spirit and we must worship him in spirit and in truth.

By definition g d can not be defined

I guess I don't
I guess that's easier
And how do you define, the indefinable

But I guess if you pushed me
Then yes, god is love
And divine manifest
As is Goddess

Y are you squashing g d in to you (maybe greet but) finite mind?!

uh...No


I think, everyone who believes in God defines God according to their own belief no matter how others define it.

By definition? Can't be defined?
By definition, God is a noun:
1.
(in Christianity and other monotheistic religions) the creator and ruler of the universe and source of all moral authority; the supreme being.
2.
(in certain other religions) a superhuman being or spirit worshiped as having power over nature or human fortunes; a deity.

Inside the head, God (if you believe in one) is much more than a dictionary definition.
Inside the head, many define God as something purely unique and personal.
How do you define God (inside yer head)?

So, your God is the "Q" from Star Trek: The Next Generation?
The most familiar "Q" is portrayed by John de Lancie.

Q is really close to defining God. Except they are a race and not one supernatural being.

Oh Benevolent
How could I possibly forget that
An absolute fundamental aspect to god / gods / goddess / goddesses ,for me, is benevolence

Your so sweet. Benevolence is all good too, kind of like "Mercy is greater than judgement. How we need to learn that...

Is, was and always will be.

We human love mysteries. Daniel caught a glimpse of him, John the Revelator also, and Christ told his disciples what he looked like. Do we need a definition other then understanding what the bible tells us?

{Psalm 96:5 For all the Gods of the nations are idols...} Something to keep in mind. Paganism is not of God but of the Nations, who created THEIR Gods for having no God.

Must one follow religion to believe in God?
Which religion?
Why?

The most important aspect of God is what he tells us of himself. "His righteousness is everlasting .. meaning that he is a just God and acting according to knowledge for ever.
Here is the proof: Gal. 6:7 Be not deceived ; God is not mocked. For whatsoever a man soweth , that shall HE ALSO REAP. That's the justice of God, hence no one will escape his judgement.

God also tells us in the bible that many souls complain before him for the unjust that has been done to them, while on earth. He will therefore act accordingly. We must therefor repent for our sins and DO his will.