Is Faith Rational?

The Bible makes it very clear that it is important, yes critically essential, that a person know God in order to find salvation. Three passages of scripture readily come to mind:

Jn. 17:3: “And this is eternal life, that they may know You, the only true God, and Jesus Christ whom You have sent.”

Heb. 11:6: But without faith it is impossible to please Him, for he who comes to God must believe that He is, and that He is a rewarder of those who diligently seek Him.

2 Thes. 1:7b-9: when the Lord Jesus is revealed from heaven with His mighty angels, in flaming fire taking vengeance on those who do not know God, and on those who do not obey the gospel of our Lord Jesus Christ. These shall be punished with everlasting destruction from the presence of the Lord and from the glory of His power,

Furthermore, in 1 Pet. 3:15, all Christians are commanded to be ready to give a “defense” for the reason of their hope in Christ. The word “defense” is from apologia, which means “a speech in defense of what one has done, or of the truth in which one believes”. (Also, see the use of this word in Acts 22:1; 1 Cor. 9:3)

Quite frequently non-believers attack the veracity of the New Testament and claim that it is unreliable and cannot be trusted. Hence, a Christian’s “faith” is labeled “illogical”; something only worthy of an intellectual “simpleton”. For example, noted author Mark Twain is reported to have made this comment about God’s word:

“The Bible has noble poetry in it; and some clever fables; and some blood-drenched history; and a wealth of obscenity; and upwards of a thousand lies.”

Thus, it is very important for us to consider this question: Does a Christian’s faith have an intelligent and rational basis? If we cannot answer this question in the affirmative all of our activities aimed toward knowing God are futile and vain. Also, if our faith does not have an intelligent and rational basis, Peter’s instructions in 1 Pet. 3:15 are not worthy of one second of our time or one ounce of our energy.

First, I would suggest to you that the Christian’s faith does have an intelligent and rational basis, because God’s word, the basis of faith (Rom. 10:17); appeals to a man’s heart and mind. It does so because it is based on truth.

Mt. 22:36-38: "Teacher, which is the great commandment in the law?" Jesus said to him, " 'You shall love the LORD your God with all your heart, with all your soul, and with all your mind.' "This is the first and great commandment.

Jn. 8:32: "And you shall know the truth, and the truth shall make you free."

Contrary to what many “intellectuals” believe, one does not have to commit intellectual suicide in order to have Biblical faith! Again, Mr. Twain once sarcastically remarked that:

“Faith is believing what you know ain't so.”

In some respects, Mr. Twain was correct. His definition of “faith” is one of the legitimate definitions listed in Merriam-Webster’s Collegiate Dictionary. Here one definition of faith is a “firm belief in something for which there is no proof”. However, the type of faith spoken of in the Bible is not this “blind faith”; notice what is said of faith in the Bible:

Heb. 11:1: Now faith is the substance of things hoped for, the evidence of things not seen.

Acts 1:3: to whom He also presented Himself alive after His suffering by many infallible proofs, being seen by them during forty days and speaking of the things pertaining to the kingdom of God.

Jn. 20:30-31: And truly Jesus did many other signs in the presence of His disciples, which are not written in this book; 31 but these are written that you may believe that Jesus is the Christ, the Son of God, and that believing you may have life in His name.

2 Pet. 1:16: For we did not follow cunningly devised fables when we made known to you the power and coming of our Lord Jesus Christ, but were eyewitnesses of His majesty.

A more exact definition for the Bible type of faith is given by Webster when he defines the most common synonym for faith…belief:

“conviction of the truth of some statement or the reality of some being or phenomenon especially when based on examination of evidence” (emphasis mine, cvt)

Like, Mark Twain, many people ridicule Christians for their faith. I have felt the brunt of that charge on more than one occasion. However, if we consider the facts I contend that their allegation is, at best, unfounded; and, at worst, exposes their intellectual bigotry.

Let’s consider the facts: Did you know that the scientific method is based on our second definition of faith! I can speak with some authority here: I spent six and a half years of my life obtaining a masters degree and doctoral degree. I was intensely schooled in, and expected to rigorously and meticulously employ, this methodology! Let me illustrate by outlining the steps involved in modern empirical science along with a simple example of how the scientific method is applied and the results it obtains:

Step #1: Develop a hypothesis of what you believe to be true. (Example: Cows will give more milk on diet A versus diet B.)

Step #2: Design an experiment to test your hypothesis. (Example: Feed diet A to 30 cows and diet B to 30 cows. Note: Modern scientific experimentation involves sophisticated, tried, tested, and accepted experimental designs so that the investigator removes as much “bias” as possible from the experiment (e.g., differences due to cow age, stage of lactation, etc.))

Step #3: You conduct your experiment using the appropriate experimental design and collect the data. (Example: Feed diets A and B to your 60 cows according to the experimental design and measure each cow’s milk production.)

Step #4: Analyze your data using accepted mathematical and statistical techniques appropriate to your experimental design. (Example: Apply these methods to the milk production data you collected in your experiment from the 60 cows fed diets A and B.)

Step #5: Based on the results of the analysis you determine which diet produces more milk. (Example: Your analysis determines that, on average, diet A produces 10 lbs. more milk per cow per day than diet B. So you conclude that diet A is the best diet for farmers to feed their dairy cows.)

Now, I want you to get a very important point: The scientist’s conclusion that diet A produces 10 lbs. more milk than diet B is not determined with absolute certainty. It is determined at some level of probability that the differences in milk production from feeding diet A versus diet B were a true difference and not due to experimental error (i.e., uncontrollable factors).

In essence the scientist is saying, “Based on the evidence that I have gathered, analyzed and considered I believe diet A causes cows to produce more milk than diet B.” It is extremely rare that anything can be proven to be absolutely true; for example in the sense that one can prove that 1 + 1=2.

Contrary to the belief of many, the scientist cannot offer 100% air-tight proof that his hypothesis is true. He can only offer evidence that at some level of probability it is true. This is at the heart of every statistics or experimental design course taught at any major university! I also want to make it perfectly clear: I am not demeaning honest scientific investigation. It is a wonderful and powerful tool and our world is a much better place because of it. I have personally authored or co-authored several articles published in refereed scientific journals.

The Christian cannot offer 100% air-tight proof that God exists and that the Bible is God’s will for man. The Christian can only offer evidence that must be honestly considered. But, make no mistake about it: Whether you are an atheist, agnostic, or a Christian you operate on faith each and every day! The methodologies of which I speak are employed by scientists, medical doctors, and industrialists each and everyday to test the mundane (e.g., doggy shampoo) to the exotic (e.g., latest composite materials used in the aerospace industry).


Both the Bible believer and the scientist base their faith on the same logic: a thorough examination of evidence. The Christian’s faith is not a blind faith, quite the contrary, it is a belief based on solid evidence! (Heb. 11:1; Acts 1:3; Jn. 20:30-31; 2 Pet. 1:16) The next time an intellectual bigot belittles your “faith”; hold his feet to the fire and show him that he also lives his life by the same rule of logic. I fear many brethren cower when their faith is questioned by those that appear to be intellectually superior (e.g., Dr., Ph.D., etc.). There is only one reason to cower in such a situation: willing ignorance arising from a lack of diligent study. Oh, well, that’s another article in and of itself!

By Craig V. Thomas

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