Christians where did god exist when nothing existed?

I don't mean to offend you, but you are setting this question up all wrong. Christians don't believe in the Big Bang Theory, first of all. Second of all, there was never "nothing". One of the fundamental laws of Physics is that matter cannot be created nor destroyed. The Big Bang Theory suggests that the Universe started with condensed atoms and then suddenly expanded, not that everything just "poofed" into existence-which is ironic of you to imply, considering your discrediting of God based on modern-day science.

Edit: I really respect that you replied with an educated answer, I truly underestimated you, and I apologize for that. Nevertheless, I would like to add that the the Bing Bang Theory is just that: a theory (even though I wholeheartedly agree with it). Moving on, my reply was to your specific question, obviously, but I would like to expand our arguement by bringing up the question: "What makes something real or existant?" Now I would like to shift from science to philosophy. You are basing that which is existant or real on what can be measured or what is tangible. If that were the case - that something has to have physical properties to be real - then intangible things such as thoughts and ideas wouldn't be real, which is definately not the case. Maybe God isn't made of atoms. Just my 2 cents.

Edit 2: I really do see where you are coming from. My honest thoughts on this are that I don't really believe in God, per se, but I believe that there is something supernatural or paranormal going on, not just randomness. My personal theory is that it all has to do with other dimensions, and since another dimension (if there were one, or multiple for that matter) would not necessarily have the same laws of physics. Maybe that would support a theist's belief in heaven and hell, that they aren't in this dimension. Going back to my earlier arguement, I feel like the idea of God is a bit like currency. If you think about it, money could be considered unreal. Sure, it represents bars of gold in a vault somewhere, but it's really just paper. It serves as a sort of regulation, something to organize the world. It's an idea represented with something tangible like paper. I really do think you are making an excellent point (and that a few of the answers on here are a bit too dismissive), but historically speaking, it seems that people instinctively look to a God - which is why people usually find atheist's views counterintuitive, I think.

Time and space began at the spacetime point of the big bang. There is no "before" this point in terms of space time.

So if God is to be everlasting, as is taught by Christianity, then He must a being who isn't dependent on spacetime for His existence. It's also clear from the Bible that God isn't constrained by spacetime. At one point Jesus says "Before Abraham was, I AM." This if both a statement of his deity (I AM is the Jewish name of God in the language he was speaking at the time), and a statement of his temporal existence at a time that wasn't the present.

As to the question of where he was, we kind of assume heaven is some state of existence that is separate from the spacetime continuity that we are bound by. No one is going to be able to give you a satisfying answer about "where" this is, but we really shouldn't have to, as we're not told and it's not really important.

Another important theological point about this is that God is usually considered self existent. That means that He depends on no one but Himself for existence, so he doesn't strictly speaking even need a location at all. Kind like how the number 3 doesn't need a place to exist, but the concept exists even without a location.

To the question of whether God came from nothing, I'd say that He always has existed, as implied by the fact that He's self existent. Since He depends on nothing to exist, not space or time, there is no state of affairs possible in which He does not exist.

You can't prove nothing existed and God can't be proven,such a predicament History is our only guide. Genetics will supply many enlightening things about ourselves. In the end,if you extrapolate intelligent sentient beings backward you ultimately find the first. Who might that be?

God was just there he is flawless. Logic has no reason in this case, it is way above the human mind to understand God. God created everything, he is the creator of everything no void here.

God exists outside of the universe.

Because humans have a beginning and an end we think God must have the same characteristics, he doesn't.

Your mistake in reasoning is you consider God to be a corporeal being that is extended in space.

heaven is eternal