Many Christians say that the best answer to the reason why there is a universe, and why anything exists at all, is that God created the universe and all that is in it. But if God created everything, who created God?
Surely if Christians, Muslims, and Jews are going to say that God created the universe, it’s a valid question to ask. If theists say God created the universe, surely it’s fair to ask the same question about God? Isn’t it special pleading if we don’t?
Let’s think a little bit deeper about this question. On the surface, it seems like a fine question to ask, however, it also makes some assumptions. Firstly, the question assumes that everything needs a creator. But that means that anything that created something would itself need to be created. That is, if God made the universe, he must have been created by another God, and then created by another God, created by another God, and so on. Or as Hindu mythology puts it – it’s turtles all the way down. The idea of infinite regression is built in to the question, so any answer is always going to end in absurdity. The question, by its own design, can’t be answered coherently.
There’s another assumption built into the question – that God is the type of being that needs to be created. However, in every classical idea of God this isn’t the case. God is, by definition, an uncreated, necessary being, that exists outside time and space. The question is essentially asking ‘who created the uncreated being’? Hopefully you can see that this question is problematic – it makes a category mistake. It’s like asking what version of Android my iPhone is on, or how many Snapchats I get on Facebook. There are two categories of things – created things and uncreated things, and the question assumes God falls into the category of created things.
The question has issues because it makes some bad assumptions. If God existed in the natural world of cause and effect then we would need to find an explanation for his creation, but all along classical theism has maintained God is fundamentally different, the creator and sustainer of the cosmos. As far back as Aristotle, people have recognised that the universe needed some kind of unmoved mover or ultimate first cause to kick things off, to initiate the first cause and to make the first move to bring the universe into existence.
I would understand the follow-up question though – if God can be a necessary being who doesn’t have a need to be created, why can’t we just say that about the universe? Can’t the universe create itself? Can the ‘universe’ create something from nothing? If, say, we can show that a zero-balance quantum field can give rise to the universe, doesn’t that solve our problem?
Well, no, for a number of reasons. Firstly, there is very, very good reason to believe the universe came into being about 13.7 billion years ago with a, well, you know… a bang. A big one. Even if you want to appeal to theories like the multi-verse or some type of bubble or steady state universe (an eternal universe) the Gorde-Buth-Vilenkin theorem still requires that the universe had a beginning, an initial point of expansion. If the skeptic wants to say that quantum fluctuations caused the universe, they’re still asserting that something is coming from nothing – as a rich quantum field with physical laws isn’t nothing by any stretch of the imagination. It seems utterly fantastical to say that the universe created itself out of nothing. Things that are within the natural order can’t just create themselves. It is severely problematic to try and say that the universe pulled itself up by its own bootstraps.
This is a short article, and I’m not exploring all the arguments for and against God’s existence. However, I hope you can see why the question ‘if God made the universe, who made God’ is not a helpful question, and I don’t think it passes muster as an objection for belief in God.
 Aristotle, Physics, Book VII, http://classics.mit.edu/Aristotle/physics.7.vii.html
 Laurence Krauss, Interview: A universe from nothing, http://www.npr.org/2012/01/13/145175263/lawrence-krauss-on-a-universe-from-nothing
 Arvind Borde, Alan Guth, Alexander Vilenkin, 2003, Inflationary spacetimes are not past-complete, https://arxiv.org/PS_cache/gr-qc/pdf/0110/0110012v2.pdf