What Key Arguments Are There for God’s Existence? (Part 1: Cosmological Argument)

I’m excited to start my series today on “65 Questions Every Christian Parent Needs to Learn to Answer.” Yes, I’m going to answer each one on my blog this year (amongst other posts)!

Let’s get right to question #1: What key arguments are there for God’s existence? If you can’t confidently answer that question right now in a way that doesn’t reference your personal experience or the Bible, this is a post you need to read.

Why This Question is Important

(I’ll start all posts in the series with this section.)

In today’s secular culture, the Bible is increasingly considered to be a set of ancient documents filled with inconsistencies, erroneous science, implausible miracles, and irrelevant moral standards for modern life. Its difficulties have become the stumbling block driving many young adults away from Christianity.

But what if we step back and look at the evidence for God without discussing the Bible at all? The actual existence of God is a prerequisite for the Bible even mattering. If your kids are strongly convicted of God’s existence, they’ll be far less likely to casually toss their faith aside when they begin encountering biblical or other spiritual difficulties.

All three of the arguments I’ll discuss in this series are easily understandable by kids of all ages. I’ve described each to my 5-year-olds (in an age appropriate way).

Three Major Arguments for God’s Existence

There are three major arguments used to “prove” God’s existence. Many other lines of reasoning have been used, but the three most significant you should know are the creation (“cosmological”) argument, the design (“teleological”) argument and the moral argument. In this post, I’ll discuss the creation argument. My next two posts will explain the design and moral arguments.

While this may sound highly philosophical (perhaps boring if you’re not normally into this kind of discussion), I assure you that these arguments have immense practical significance. And when you fully internalize their meaning, dare I suggest you might even find them spiritually invigorating?

Nothing has solidified my personal faith, taking me from belief to passionate conviction, like learning these three arguments for God’s existence in depth.

Outline of the Creation Argument

The creation argument provides reasoning for God based on the existence of the universe. There are three parts to remember (people state this in various ways, but the conclusion is the same):

1. The universe had a beginning.
2. Anything that had a beginning must have been caused by something else.
3. Therefore the universe was caused by something else, which we call God.

It’s quite simple on the surface, but it’s a powerful argument with far-reaching implications if true. Let’s look at each part briefly.

The Universe Had a Beginning: A Big, Bold, Hugely Important Statement

I know that sounds like a no-brainer: “Of course the universe had a beginning; how else would it get here?!”

That is the logic of our everyday experience. We know everything that exists around us had a beginning and didn’t just exist forever.

But the overall creation argument is so powerful – leading to the inevitable conclusion that there must be a cause of the universe – that many scientists and philosophers through the years have worked to show the universe is eternal (i.e., without a beginning) in order to escape the need for a cause that could be God.

Much to their chagrin, modern astronomy has shown the opposite to be true.

Science Evidence That the Universe Had a Beginning

In the 1920s, astronomers for the first time had access to extremely powerful telescopes that allowed them to discover galaxies outside of our own (until that time it was debated whether our Milky Way galaxy was the only one). Astronomer Edwin Hubble measured the distances and motions of these newly found galaxies and discovered something that had astronomical (pun intended) theological implications:

The universe is expanding; those galaxies are moving away from us, like spots on an inflating balloon.

If the universe is expanding, it implies a beginning. Why?  If you rewind the process of something expanding (think of deflating the balloon), you would eventually get to a single point – the moment the universe began. Hubble’s findings changed everything. The universe had a beginning, and you don’t even have to believe in the Bible to arrive at that conclusion.

(Note that there is other significant scientific and philosophical evidence for the beginning of the universe outside the scope of this post.)

Anything that had a beginning must have been caused by something else.

The next part of the argument – that anything with a beginning must have been caused by something else – is somewhat more straightforward. I say “somewhat,” because if you really want to get lost in philosophical arguments over whether or not things can pop into existence out of thin air, you can. (Just Google it.) But almost everyone agrees that things with a beginning are caused by something or someone else.

Therefore, the universe was caused by something else, which we call God.

Let’s recap what we have here: almost universally accepted scientific evidence that the universe had a beginning and knowledge that anything with a beginning is caused by something else. That leads us to the conclusion that the universe had to have been caused by something else.

The million dollar question: What could that have been?

A person can’t dismissively state, “It could have been anything.” Knowing what it would take to create our known universe greatly narrows what kind of cause we have to look for.

Dr. William Lane Craig, a leading philosopher who champions this argument, concludes that a candidate cause would have to match the following profile: personal (i.e., able to choose to create), uncaused, beginningless, changeless, immaterial, timeless, spaceless, enormously powerful, and enormously intelligent.

We call that God.

But if everything needs a cause, what caused God?

It’s important to understand that the argument doesn’t say everything needs a cause; it says everything that has a beginning needs a cause. In order for a cause to create a universe of space and time, that cause has to be outside of space and time (eternal). Whether you call that God or anything else, that cause cannot have a beginning itself. Something without a beginning doesn’t require a cause. It has always existed. God is the original “uncaused cause.”

In summary

The conclusion of this argument doesn’t necessarily point to the God of the Bible. Other reasoning is necessary to get from the existence of God in this sense to the existence of God in the biblical sense. But this is an important starting point for the chain of evidence that ultimately leads to Jesus being our Lord and Savior.

For a video presentation of the cosmological argument, click here (it’s stated a little differently than the version in this post, but the idea is the same). This is a great video to share with your kids if they are old enough! Also, you might enjoy playing with your kids on this site that demonstrates the scale of the universe to share just how huge God’s creation is.

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