I contend that we are both atheists. I just believe in one fewer god than you do. When you understand why you dismiss all the other possible gods, you will understand why I dismiss yours. --Stephen Roberts
The [God] that can be described is not the eternal [God]. --Tao Te Ching
Every block of stone has a statue inside it and it is the task of the sculptor to discover it --Michelangelo
As far as I can tell, no two theists believe in the same God.
Does God have a gender?
Does or did God literally speak to people?
Is God a trickster who created a universe to look billions of years older than it is?
Did God dictate the Bible word for word?
Is Genesis literal truth, truth in the language of its day, or mythology?
Does God want anything of us?
Is there a Heaven?
Do dead people come back to life?
Is God the same thing as the Universe or the Multiverse?
Is God loving? Wrathful? Both? Neither?
Are we God?
Is God in everything?
I could come up with hundreds of these questions. Maimonedes came up with 13 answers which he (sort of?) believed all Jews needed to believe, but even those are controversial.
In short, the theists are right when they say that God is unknowable. As an atheist, I agree. :)
But what's an atheist? Do I disbelieve every possible definition of God? No, I believe in love and in the Universe and some people say God is love or God is the Universe.
All I can do is describe what I don't believe in.
Perhaps that's ultimately a path to a God.
When I was a smart-assed computer science student, I was faced with a test question which I was sure had a mistake in it. Instead of trying to figure out if I was misunderstanding it or asking for clarification, I decided to set out disproving the question's consistency.
I wrote a page and a half of text, numbers, and equations trying to prove that the question was wrong. Half an hour later, though, I reached the end of my calculations and found that not only was the question right, but I'd reached the correct answer by trying to disprove it.
Maybe theism is the same way. Maybe some theists just saw the question "What is God?" and quickly reached the right answer.
But for me, all I can see right now is that the question rests on a false assumption. Perhaps by trying to disprove it, I'll return to theism. (I doubt it, but I must admit it's possible.) For now, all I can do is figure out all of the gods and religious claims I don't believe in.
Theists who want to know God should take atheists seriously. We might turn out to be your best allies.