Yeah, if we were wrong about the Big Bang, and IF the universe was eternal.
The Big Bang is a theory based on mathematical models created by astophysicists, with some supporting evidence derived from observed changes in that part of the universe about which we know. I am no physicist or mathemetician, either one, but they believe that if they use mathematics to “run the clock back” on those changes that are observable, they arrive at a moment in time in which the universe was concentrated into a tiny speck of incredible energy which they expanded (or “exploded”) with some of the energy “congealing” into matter.
Now, maybe that’s reality and maybe it isn’t, but our faith does not depend on its being true or untrue, either one.
Most physicists think they can’t go back in time past that event because everything would have been changed by the event itself; all the physical rules and everything. Some think they can, but not by anything observable; only by mathematical constructs.
Some think the Big Bang was preceded by fields of energy corresponding to dimensions which, in colliding, created the Big Bang, but which are otherwise unknowable. Some think those fields go out of existence and back into existence by processes nobody has ever witnessed or ever will, but which, to some, seem to work out on the math chalkboard.
So, if they were able to do what most of them think they can’t do, and go back and back and back some more into time, having any idea at all of what it looked like or how it worked becomes ever more remote.
So, in talking about whether the universe was “eternal” creation by God cannot be excluded because if the God of the Christians is real, then His means of creation and His means of knowing His own mind and intentions, are not knowable to us. Quite possibly, not ever.
If God is infinite, we will never plumb His depths even in a trillion billion years of absorbing his self-revelation to us in heaven. Never. We’ll likely know a whole lot more than even the most advanced physicists do now, but we may never really know how God conceived of the universe (and whatever else He created). The likelihood is we’ll be awed by what we do learn, and enjoy it. But we can’t know God as God knows Himself or we would be Gods ourselves.
I am personally not bothered in the slightest by whether there was or was not a Big Bang or whether there were eleven dimensions or only ten, or perhaps only one, or whether something about the creative process caused the universe to wink out and then flash on again in series, or whether something we might call “the universe” existed in some manner in the Mind of God forever.