Can Faith Trust Reason?

One Sunday afternoon5, my wife and I were out to lunch at a local restaurant. We brought with us several books (among which was a bible) and a man (we’ll call him Bob) stopped us to ask what we were reading. Within minutes we were in a full scale theology conversation.

Something in the conversation struck me. It happened after I mentioned that “we can use our reason to make sense of our faith.”

“Reason? That’s how the world thinks,” Bob countered. “We Christians believe in God through faith, not reason.”

Shortly thereafter, the conversation ended and we went our separate ways. I was stunned by Bob’s comment. He rejected the idea that Christians could grow in their faith with the use of logic (i.e. human reason). What I find more shocking, however, is that I’ve heard undertones of this belief while talking with many other Christians. It’s as if people are afraid to apply what they know of the natural world to what they know of the supernatural.

I don’t entirely blame people for believing this. How many scientific “discoveries” are we told disproves the existence of God? How many people have pitted the theory of evolution against the story of Adam and Eve? “We don’t need faith,” some argue, “we have science!”

Even some Bible verses appear to be backing this belief. St. Paul himself said that “the wisdom of this world is folly with God” (1 Cor 3:19), and that he lives “by faith in the Son of God” (Gal 2:20).

So what does this mean for Christians? Do we reject reason, holding fast to faith? Can reason pervert faith? Is faith compatible with our natural reason?

If you find yourself asking any of these questions, know that you’re not alone. Many  people (like Bob) struggle to see how faith and reason work together.

People often feel as though they must keep faith and reason separated. But God created man with the ability to use faith and reason, and he found it to be “very good” (Gen 1:31). So how should Christians respond to the dilemma between faith and reason? Let’s take a look.

Two Sides of the Same Coin

What is reason? Taken straight from the dictionary, reason is “the mental powers concerned with forming conclusions, judgments, or inferences”.1 If we were to boil this definition down, we might say that reason is a way of knowing something. Reason helps us to make sense of the world around us by inferring information, making sound judgements, and forming conclusions.

Does this sound like the scientific method to anyone? It should. The scientific method uses reason to learn about the world in which we live. To be clear, the scientific method is only a subcategory of human reasoning. It doesn’t embody all of human reasoning. But that’s a subject for a different time.

So reason is concerned with knowing things using our minds.

Then what is faith? Faith is a little trickier to define, as it can have a wide range of meanings. The dictionary defines faith as “belief that is not based on proof”.2 The Bible offers a great explanation for faith as well, as the author of Hebrews says that “faith is confidence in what we hope for and assurance about what we do not see” (Heb 11:1).

So pulling these definitions together, faith is belief in something, though it isn’t necessarily proven by reason. So, as we saw with reason, faith is just another way of knowing something.

To drive this home, let’s see some of the ways we use faith and reason:

Reason (this is an easy one): Two plus two is four. You know that is true because your human reason tells you so. Like I said, this is an easy one.

Faith: It is your birthday, and a friend gives you a $20 gift card to your favorite restaurant. Do you know that it actually has $20 on it? It could be a fake. Or it might only have $10 on it. But (if we are being realistic) this isn’t how we think. Your friend didn’t prove that it has $20 on it, but you can trust your friend and accept it by faith.

So faith and reason are just two ways that we come to know things. Reason allows us to know things through our intellect; faith allows us to know things through trust.

Fun fact: You might find it hard to believe, but we even know many scientific “facts” by faith, even though reason was used to discover them. For example, have you ever personally measured the weight of a neutron? Neither have I. Yet scientists tell us what they weigh (1.6750 x 10-24 g, for those who are wondering). This is information we know by faith because we rely on others’ research and honesty.

Reality Doesn’t Contradict Itself

It’s time for another quick definition: Reality. What is reality? Simply put, reality consists of things that are real. So if I were to say “all of reality”, I am referring to all real things; all things that are true; all things that simply are. We use our faith and reason to know things that are real. That is, we learn reality through faith and reason.

It’s time that I introduce to you a friend of mine. His name is Aristotle, and he has opinions about the nature of reality. Aristotle taught us something known as the Principle of Noncontradiction. It can be stated as follows:

“It is impossible for the same thing to belong and not to belong at the same time to the same thing and in the same respect.”3

(Note that I didn’t say he was easy to understand). The Principle of Noncontradiction says (simply put): something cannot be true and false at the same time. Let’s use a quick example:

Let’s say I put a box on a table in front of you. I then tell you that I may or may not have put an apple in the box earlier. Is there an apple in the box? The principle of noncontradiction says that there either is an apple in the box or there isn’t. It can’t be both. What is true cannot, at the same time, also be false.

So the takeaway here is: knowledge from faith and reason can’t contradict. They are all truths that contribute to reality. If they do contradict one another, either our faith or our reason is wrong.

Jesus: The Eternal Word

Reality doesn’t contradict itself because it all comes from the same source. And that source is God. Because everything came from God, reality is naturally unified. One of Jesus’ titles tells us as much.

We have all heard of Jesus being referred to as the “Word” of God (John 1:1). But what many don’t know is that in Greek, the word for “word” (logos) has multiple meanings. Logos means both “word” and “reason”.

Jesus is referred to as the Logos frequently through St. John’s Gospel. From the very beginning of the Gospel we see the reference three times:

In the beginning was the Word (Logos), and the Word (Logos) was with God, and the Word (Logos) was God. He was in the beginning with God. All things were made through him, and without him was not any thing made that was made (John 1:1-3).

The idea that Jesus is God’s Logos (God’s Word; God’s Reason) is packed with implications. For starters, we can see that Jesus isn’t merely God’s spoken word, but also God’s interior logic; the Divine Reason that gives meaning and order to creation. Jesus is the very Reason that shapes all of reality!

Faith and Reason in Harmony

At the end of the day, nobody wants to believe a lie. Nobody wakes up saying “gee, I hope someone will deceive me today.” We have a natural tendency to desire truth. And we sometimes favor things that we can prove, things known by reason. I believe that’s why so many people distrust faith. But we simply don’t live by reason alone. It’s not how humans are programmed (just imagine going on a date with someone who insists that you “prove” every detail about yourself on the spot).

But we must be careful not to throw the baby out with the bathwater. It is freeing to be able to believe something by faith, by mere trust. But reason tells us who and what we can trust. Conversely, faith helps guide our reasoning, by illuminating the truth (like seeing the answer at the back of a textbook). Faith and reason build on each other and temper each other.

So Christians need not fear reason. Properly applied reason will never disprove a truth known by faith. God created all truths to be in harmony with one another, whether they are accepted by faith or reason. In fact, Jesus revealed himself to be The Truth (John 14:6), from which everything was created (John 1:3). By discovering truth, we slowly discover the One Truth, who calls us to know him.


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1. “Reason.”, n.d. Web. 11 Mar. 2017.

2. “Faith.”, n.d. Web. 12 Mar. 2017.

3. Metaph IV 3 1005b19–20