By buying into "billions of years" — even squashed into "six days" — you're assuming the veracity of Big Bang cosmology. You would concede the possibility that the theory of the Big Bang could be falsified, right? That's a scientific approach. If so, there's no need to describe God as doing billions of years worth of work.
OK.
Matter from nothing is a miracle by definition, regardless of how long it took.
I wrote that tongue-in-cheek, since we are discussing the creation of the universe.
The backdrop here is that He created everything, so that is already the most profound of miracles, even, in a way, more profound than Christ's Resurrection, which is the most important event to occur within creation. So to my mind, there's nothing stopping God from doing '13 billion years of work' in six days.
It's the time/velocity/distance formula at work. We know the distances well enough and lightspeed seems to have an upper limit. If those numbers are as they appear, billions of years are necessary.
And of course you see that my view has no trouble with this, since under 10,000 years ago, and fully grown universe was set in motion, including star light that appears to have been traveling for billions of years, but was as new that first week as everything else was.
Sure. I don't think we disagree in any significant manner, but it looks like you're seeking a metaphor to explain things, whereas I would look to science.
First, I proposed an idea about how science will come to confirm the Christian faith, if given enough time before the Lord returns:
Here's what I think's going to happen. We can already see 'over 13 billions years in the past' through careful manipulation of the Hubble telescope. I think we will, who knows exactly when, but we will be able to see light from the mythical birth of the universe, and the images we will see then will be of heaven, and of Christ sitting on His throne, at the right hand of the Almighty. And we'll all at that point do a little quick math and realize that there hasn't been enough time for Him to get to heaven if He traveled at the speed of light, so He must have traveled much, much faster than the speed of light to be already sitting on His throne by the time the image of Him reached the earth. This will confirm everything.
It's a pet theory, but it's one that grips my imagination.
fwiw
And secondly, you're probably onto something with me wanting a 'metaphor,' but there's not a well-defined line between wanting a metaphor, and the truth, since what I'm trying to do is systematize, organize, interpret a wide range of varieties of scientific observations into a nutshell, and that nutshell, especially in the vacuum of precise knowledge of how it occurred, is going to resemble a metaphor, in order that we can understand the concept without knowing its true details.
Invoking the metaphor I've made, between the age of the universe, and the apparent age of Adam and Eve on say day eight, what science is trying to do cosmologically, is like taking a full grown human being, and through measurement, observation, experiments, try to determine precisely what a fertilized zygote in the womb looked like.
We know what we look like at conception, and this is part of how we can know, even apart from religion, that unqualified, deliberate abortion is tantamount to murder---but it is because we are reproducing actively. We do not know of any universes that are being conceived, gestating, being born, and so we are never going to be able to get confirmation of our cosmologies in the way that we confirm how human beings are generated.
But also, how was Adam created? Was it in the same way that babies are born today, did He just speed up the process, bringing Adam all the way from fertilized egg to full grown man in a day? Or was Adam's creation a singular event, never to be repeated, strictly for the purpose of creating? We don't know that, and we don't know how the universe was created either. I am as are you, trying to integrate what science discovers, with what God has said, and 'the scripture cannot be broken' (Jn10:35KJV), as Christ said. So whatever science thinks it knows, I forbid myself from accepting anything that contravenes God's Word.