Since it was proposed by Fr. Georges Lemaître, the Big Bang has been common in discussions of the existence of God.
The reasons are obvious. The Big Bang looks like a plausible beginning for the physical universe. Things that begin need causes. The beginning of the physical universe would need a cause, which would seem to lie outside the physical universe. This coheres well with the Christian claim that God is a non-physical being who created the physical universe.
The argument has been elaborated various ways, but that’s the basic idea.
One of its fans was Pope Pius XII, who elaborated a version of it in a speech about this to the Pontifical Academy of the Sciences back in 1951.
It’s basically a version of the Kalaam cosmological argument that uses evidence from modern cosmology to support the premise that the universe had a beginning.
It even resonates with the “Let there be light” moment in Genesis.
I think that there is a proper role for the Big Bang in discussions of God’s existence, but it has to be used with some caution.
Here’s why . . .
“Let There Be Light”?
One temptation is to identify the Big Bang not just as the moment of creation but specifically as the creation of light in Genesis 1. That’s problematic because Genesis does not portray the creation of light as the moment the world came into existence. Let’s look at the text:
1 In the beginning God created the heavens and the earth.
2 The earth was formless and void, and darkness was over the surface of the deep, and the Spirit of God was moving over the surface of the waters.
3 Then God said, “Let there be light”; and there was light.
In the text, the earth already exists in a formless and empty state, with a deep of waters that has a surface, which the Spirit of God hovers over. Then light gets created.
So Genesis depicts the creation of light happening when the heavens and the earth and its waters already exist. At least that is how the text depicts it. You can argue that this isn’t to be taken literally, but that only makes the same point another way: We shouldn’t be too quick to identify the Big Bang with the creation of light in Genesis. We have to be careful about mapping Genesis onto modern cosmology.
In fact, Pope John Paul II warned specifically against trying to draw scientific conclusions from the creation account in Genesis 1:
Above all, this text has a religious and theological importance. It doesn’t contain significant elements from the point of view of the natural sciences. Research on the origin and development of the individual species in nature does not find in this description any definitive norm or positive contributions of substantial interest [General Audience, Jan. 29, 1986].
The Moment of Creation?
There is another thing we need to be careful about, which is identifying the Big Bang as the moment of the physical universe came into existence.
It may well have been. I would love for us to find a way to prove that scientifically.
But we’re not there at present.