How many things do we just accept without ever reflecting on them? For instance, why do clouds, supposedly made up of water vapor, look like vast cotton balls floating in the sky? (Alas, I have discovered that a close up view looking out the window of a Delta flight does little to dispell the mystery.) As puzzling as this and countless other things may seem, rarely do we stop to ponder how cloudy our understanding really is. (Get it? How cloudy? It’s a pun!) Sometimes we need somebody like Calvin to ask the obvious questions.
Enter Jerry Rivard. Where countless Christians would nod blankly when I inform them that God exists necessarily, he just scratches his head. “I agree” he writes “that the universe is pretty amazing. But I don’t agree that God is either less amazing or necessary. Why is God necessary? (I’d really like to understand why people think that.)”
How many Christians do you think can field such a fine and direct question? Alas, probably not as many as should be able to. But I’ll happily field it.
First, let’s start here. Imagine somebody asking you “Why does a triangle have three sides? Why not four? Or six?”
You’d reply: “Because that’s how the concept of triangle is defined. Four sides yields a different object altogether. In other words, the statement ‘All triangles have three sides” is analytic. The predicate is simply unpacking content contained within the subject, the concept itself. There isn’t any more answer needed than that.
Now there are different concepts of God. Think of these concepts as analogous to different shapes, one a triangle and another a square. On some of these concepts God is a contingent being. Mormonism holds a concept like this. (Indeed, Mormonism goes much further by claiming that Yahweh evolved from being a man to become a god. But save that story for the next visit from the Mormon missionary.)
The concept of God that is shared by classical theism — a concept which is to be found in the major western monotheisms of Judaism, Christianity, and Islam — is different. On this view God is a necessary being. In other words, God must exist. God cannot fail to exist. God exists in all possible worlds. And thus God has always existed and God will always exist.
So think of the contingent God concept as the square and the necessary God concept as the triangle. Now consider Jerry’s question again — “Why is God necessary?” — and you’ll see a parallel with the question “Why do triangles have three sides?” Because that’s how God is defined in classical theism.
Ahh, but haven’t we opened a Pandora’s box? Based on the fact that there are some pretty square concepts of God out there, why think the triangular God is the right one? So we tweak Jerry’s question as follows and keep going: “Why think the concept of God as necessary in classical theism is correct?”
I’ll give you a couple reasons why. First, intuitions regarding the concept of God. Rewind to the ancient Greek philosophers for a minute. Folks like Parmenides, Plato and Aristotle recognized that the pantheon of squabbling deities in Greek mythology cannot be ultimate because they are no better than us. Reading of the goings-on up on Mount Olympus is actually a lot like watching “Days of Our Lives”: who is sleeping with whom? So and so did what? And so on. So they recognized that if something is to be considered God it is to have a moral perfection not possessed by the finite, petty, contingent deities of popular piety.
By starting out on this road of fine-tuning what we mean by “God” in terms of perfection we eventually arrive at the concept of a being that is perfectly good, maximally powerful, and fully knowledgeable. But now a question: does it make sense to think of this perfect being as contingent, that is as such that it might not have existed? That makes no sense. It’s like describing the perfect birthday party but adding at the end, “But there’s no birthday cake.” Surely if we are to talk of a being of perfection who differs from finite creatures in terms of goodness, power and knowledge, then we must also speak of that being differing from us in terms of existence: in other words, that being must exist necessarily.
That brings us to our second point for holding to this concept. We have a contingent universe around us. All the evidence suggests that the universe and its component material parts, energies, laws, et cetera do not exist of necessity. Rather, they are contingent. So what explains their existence? To appeal to more contingency merely begs the question. Eventually we have to arrive at an answer in terms of something which exists of necessity. Unless you’re content ultimately to respond to Calvin “The clouds just are white ‘n’ puffy” there must be some explanation.
A blind necessitarian explanation is of not much help. Here’s one reason why. The universe sprung into existence 13.8 billion years ago. Why not 4 billion or 40 billion years ago? Why 13.8 billion? If we appeal to a necessitarian event cause as our final explanation we must ask what triggered that necessitarian event cause 13.8 billion years ago rather than any other time. And that sends us off on another type of infinite regress.
Ultimately we need to appeal to a cause that is also an agent (like you and me) but also existing of necessity (unlike you and me). And that’s where God as defined in accord with our great-making intuitions enters the picture.
So that’s a brief primer on two reasons why Christians believe God is necessary.


