Arguments For (and Against) God’s Existence

Approximate Reading Time: 9 minutes

(This article also includes a podcast discussion. Click the play button below, or subscribe and listen on your Apple or Google podcast app.)

History is filled with stories of those who came to Christ after first being convinced of God’s necessary existence. Likewise, there are many who have fallen away because it made more sense for Him not to exist. Let’s take a broad look at some evidence for why He must exist, as well as common arguments against Him. Note that a future article may go deeper into each of these, but for today I just want us to become familiar with the common arguments that exist.

Logic and reason are on our side

We are destroying speculations and every lofty thing raised up against the knowledge of God, and we are taking every thought captive to the obedience of Christ, (2 Corinthians 10:5)

There’s a certain temptation to avoid things like logic when it comes to our Chrisitan walk. We say things like “I don’t need logic, I just need Jesus.”

However, God calls for us to defend our faith, knowing why we believe what we believe. Emotions aren’t evidence of God’s existence any more than they prove the Greek gods exist. If God created the world according to truth and reason, then His followers can’t reject those very things that God loves. So let’s look at some evidence we see for God’s existence, followed by argument people make against Him.

Why God must exist

The Moral Argument – We know right and wrong

The Bible is clear that God establishes right and wrong. Many humorously bring accusations against God, claiming that He is an immoral, perhaps even evil, being. Yet we know that good and evil are, in fact, defined as whatever God does and doesn’t approve of.

For when Gentiles who do not have the Law do instinctively the things of the Law, these, not having the Law, are a law to themselves, in that they show the work of the Law written in their hearts, their conscience bearing witness and their thoughts alternately accusing or else defending them (Romans 2:14-15)

In creating us, the standard of right and wrong has imprinted part of His nature upon us. People around the world, since the beginning of time, have instinctively understood some universal truths about right and wrong. Things like theft, murder, and adultery have regularly been seen as wrong. Likewise, self-sacrifice, kindness, and generosity have been praised. Certainly, some cultures have created a worldview that praised things which are evil (such has human sacrifice with the ancient Aztecs), but it’s obvious that morality is a universal truth.

The argument for God is that we have no reason to inherently hold to morality. Some would argue that morality is developed by culture, but if we keep going backward it just makes no sense that a) we should have developed any more morality than animals, and b) that cultures around the world, especially isolated societies, should commonly agree upon certain moral standards. It’s clear that an external source is responsible for the universal and continued sense of morality.

Cosmological Argument – Every beginning has a beginner

Look at that thing on your left. If it’s a wall, person, tree, or anything else that you can touch, there is one thing you know about it: it didn’t just spontaneously occur. The laws of the universe operate under cause and effect – whatever happens or exists is because something caused it. Someone created that wall, that tree came from a seed, and that person was born. 

Think of everything in existence as a moving ball – that ball didn’t just start rolling on its own. Gravity, wind, or an external force had to push it and cause it to move. We’ve never seen anything in the world and considered that it possibly popped into existence from nothingness. Everything has a beginning, and everything has something that came before it and caused it to be. 

Everything exists because something caused it to exist. And that cause… has something else that caused it. If we were to take one object and constantly trace its cause-and-effect, we would see causes all the way back to the beginning of the universe. But that forces us to ask one very important question – what caused the beginning of the universe? And whatever caused the beginning of the universe… what caused that to exist?

The evidence for God is this: in order for everything to exist, there has to be one cause that wasn’t created by something else. In order for time to move forward, we must be able to stop tracing cause-and-effect. Thus, God is often called the “Uncaused Cause” and the “Unmoved Mover.” In other words, in order for everything to exist there must be one being who wasn’t caused or created by something else, and that being must be the one who caused and created everything else.

Ontological Argument – God must exist because He must exist

If I’m completely honest, this is probably the weakest “classical argument” for God’s existence. I never use it personally, but it’s important to understand because of how prominent it still is today. I’ll try to simplify it, but don’t be discouraged if you’re still left saying “Huh?”

Imagine that God exists in all His perfection. He is all-powerful, filled with love, demands justice, etc. Everything we know about this perfect God is true, including the fact that He exists. Now imagine all those things about God, except that now He doesn’t exist, and is merely a product of our imagination. Which one is more perfect?

That’s the basic idea of the Ontological Argument – we can’t imagine a being any more perfect than God, but He’s even more perfect if He actually exists. And since we can’t imagine something greater than a perfect being who exists, He must exist.

The best way to use this argument isn’t against an atheist, but against another Christian. This doesn’t so much prove God exists as it dispels doubt for those who may struggle with faith. If we believe an almighty being exists, the perfect God of the Bible is the one who makes the most sense.

Teleological Argument – Things are too complex to be random

This argument goes nicely with the Cosmological Argument. It’s classically explained with a pocket watch, but let’s modernize it with an iPhone. 

If you’re walking along a beach and find a perfectly-working iPhone, you will never gasp and exclaim “Wow, look what randomly occurred from the wind and lightning mixing with dirt and sand over a long period of time!” When you find something as complex, functional, and purposeful as an iPhone, you know that it was designed by an intelligent being.

This is the argument for God. Everything in existence, from the grandness of the universe to the complexity of our DNA, is too complex and purposeful to exist by chance. The idea of something as complicated as our eyeball developing randomly, no matter how much time it took, is impossible. It’s like claiming that if you throw a pile of Legos in the air enough times, they will land in a 1:1 replica of the Cistine Chapel. Yes, it could happen with an infinite amount of time and perfect circumstances, but if we see a Lego creation we instinctively know someone created it.

And of course, that’s just looking at one complex thing and realizing how unlikely that chance + time could create it. When we look at absolutely every aspect of our universe, it becomes more and more obvious that an intelligent designer is behind billions of objects with their own unique and complex design. 

Why God doesn’t exist

(Note that these don’t really don’t have official titles like the arguments for God because they are more like counter-arguments than anything else. As a result, these argument are also shorter because they aren’t trying to explain anything.)

Unseen – A lack of evidence

This is the #1 faith killer. I know my dog exists because I can touch and hear him. I can prove my house exists through pictures or letting someone directly interact with it. But the “evidence” of God’s existence is based on a set of assumptions, not physical proof. Christians may talk about a personal relationship with Christ or knowing God exists in their hearts, but the reality is that we can’t demonstrate that a literal being named “God” exists.

Occam’s Razor – Don’t complicate the simple

Occam’s Razor is an important part of logical thought. It simply states that if something can have a simple and obvious explanation, that’s the most likely explanation. “If you hear a rumble in the sky, assume it’s thunder and not a spaceship.” When we apply this to the universe, the argument is “If the existence of the universe can be explained through natural means, there’s no reason to explain it using the supernatural.”

In other words, things like the Teleological Argument ignore the fact that all these complex things could occur if given enough time. Using God as an explanation may be easier, but it adds something extra where it’s not absolutely required. Thus, God isn’t required to explain the existence and complexity of the universe, so He doesn’t have to exist.

Imperfection – Why do evil and suffering exist?

If God is perfect and loving, why does He allow the world to exist in its current state? We have rape, murder, starvation, war, and suffering everywhere. Even those who follow Him die to cancer, natural disasters, and senseless violence. How can all of this be explained?

If God exists, then either He is all-powerful but refuses to do anything about it, making Him a monster. Or he hates evil but can’t stop it, meaning He’s not really God at all. What other explanation is there?

What makes the most sense is option three: God doesn’t exist, and everything we see in the world is just a result of randomness and human nature.

Impossible Beginnings – Who created God?

We’ve discussed that God must be the “Uncaused Cause.” But really, that doesn’t make sense. How could a conscious being exist for eternity? Modern science and philosophy agree that an eternal universe is impossible. 

The why or eternality is fairly complicated, but in a nutshell it’s like having a movie with no beginning. If we hit the rewind button, we would never stop rewinding, and thus the movie would never be able to move forward because it would have no starting point. 

Thus, God existing eternally is completely illogical. Likewise, He would not be an all-powerful being if He required a beginning, and we would then be forced to ask “who created God?” We can’t say “everything must have a beginning” and then make a special allowance for God.

Paradoxes – God can’t be everything we say He is

God is all-powerful, meaning there’s nothing He can’t do. Thus, He must be able to make a rock so heavy He can’t lift it. But if He could make such a rock, then He must not be all-powerful because He wouldn’t be able to lift it. But if God can lift any rock… then it means He’s not powerful enough to make one too heavy. 

God can’t exist because everything we say about Him is incompatible. Having so many ultimate attributes (power, love, knowledge, eternal existence, etc) creates ridiculous situations like the heavy rock. As a result, people who believe in Him must create certain rules and limitations to try to make sense of it and remove these paradoxes.

The end?

These aren’t the only arguments for each side, nor have I gone deep into each one. Each argument for God requires an article on its own, and those arguments against Him likewise deserve a dedicated time to explain and disprove. However, these are all worthwhile arguments for both sides to consider and be prepared to defend. 

As followers of God, it’s on us to make sure that our faith is built on solid reason and understanding, not emotions and subjective feelings. If God loves truth, then His followers must likewise love and pursue truth as well. Our faith will always stand firm not because of what we believe, but because we know why we believe it.


but sanctify Christ as Lord in your hearts, always being ready to make a defense to everyone who asks you to give an account for the hope that is in you, yet with gentleness and reverence (1 Peter 3:15)

This article is part of the series “65 Theology Questions People Will Ask You.” Click the link to read more informative articles like this one!