Communism's
philosophical bases are materialistic, as you can see here:
http://www.marxists.org/archive/lenin/works/1908/mec/one4.htm#v14pp72h-075 It all started with Marx's upside-down interpretation of Hegel and of metaphysics, but the point is that matter itself plays the role of the divine.
Capitalism isn't an ideology, a religion, a movement or anything, is just the way by which humanity sustains itself through economic activity that consists in accumulation of capital. For example, even a "socialist" --in proudhounian terminology-- economy with no private property would be capitalistic since there is capital (means of production) and it is accumulated over time (you develop technology to further develop technology with the goal of increasing material comfort).
A God that existed before the timespace and matter existed is the ultimate cause, the cause without a cause, so it didn't "come from" anything, but that also makes it
inconceivable, it transcends reality and, in christian narrative, only becomes immanent when Jesus is born. It's a premise; you can either accept it to be true without any "proof" (you have
faith in it) or deny it, also without any proof, but by doing that, by negating something that precedes matter you're merely stating that matter is the ultimate cause and you already know what that means.