For over a century the global community has been arduously attempting to either combat science and faith or find harmony between the two. This same argument can be said for faith and reason. Since the inception of philosophy, the Church founders and fathers have been defending the faith utilizing theology and reason. Therefore reason, in and of itself, is one of the pillars of the biblical faith and undergirds all theological dogma. Reason acts as a countervailing substructure to Christianity through which sound biblical doctrine is illuminated to provide effective discipleship. This essay will promulgate this thesis by showing where reason was used in both the Old and New Testaments to point to God’s existence, saving grace, and worship. Finally, this author will postulate a synthesis of where and how faith and reason live in Christianity and aid in the sanctification process.
It is best, to begin with simple and theological definitions of what faith and reason are. Before biblical narrative and exposition are postulated, it is necessary to understand what terms mean in their theological backdrop.
People often parody faith as something that is believed for which there is no proof. One of the most common misrepresentations of faith is that it is blind. The perennial scripture for what faith is can be found in the book of Hebrews; “Now faith is the assurance of things hoped for, the conviction of things not seen” (Hebrews 11:1). This is a beautiful scripture but it fails to fully capture what biblical faith is in its entirety. Moreland and Craig give an almost perfect explanation of what faith encompasses:
The biblical notion of faith includes three components: notitia (understanding the content of the Christian faith), fiducia (trust), and assensus (the assent of the intellect to the truth of some proposition). Trust is based on understanding, knowledge, and the intellect’s assent to truth. Belief in rests on belief that. One is called to trust in what he or she has reason to give intellectual assent (assensus) to. In Scripture, faith involves placing trust in what you have reason to believe is true. Faith is not a blind, irrational leap into the dark. So, faith and reason cooperate on a biblical view of faith.
Faith is so much more than believing in something that can not be scientifically or empirically proven. It is about a declaration of trust in the sovereign God of the natural and supernatural world who holds all things in its place (Hebrews 1:3).
The concept of reason is a bit less complicated but a bit more secular. Reason has been debated and postulated by some of the world’s greatest philosophers, theologians, and scientists. A detailed definition of reason can be stated as follows:
The faculty or power that allows humans to think or deliberate, to see the connections between propositions and draw proper inferences. Reason can be taken in a narrow or a broad sense. In the narrow sense reason is often contrasted with sensation and memory as the power to make inferences, and truths that are known by reason are those that are known a priori or purely by reflection. In a broader sense reason refers to the human faculties that make knowledge possible, including memory and sensation.
Therefore, Christians use reason to answer, inquire, explicate, and promulgate the Christian faith. Reason is by the means with which faith-based communities practice their theology manifestly.
Now that faith and reason have been demarcated by Christian philosophy, it is incumbent to show proper evidence where the Old and New Testaments show how biblical authors and characters used both faith and reason to show the majesty and truth of God.
God is The God of Reason – Old Testament
A common misconception of the God of the Old Testament (YHWH) is that He is capricious, whimsical, and tyrannical. If true, this would make the creator of all things a very unreasonable entity. Although a point-by-point refutation is outside the scope of this essay, this author will provide three distinct theories that prove otherwise and shed some light on how faith and reason are not only complementary but intertwined.
God the Creator of Reason
The world is governed by a series of laws. From these laws, humans use thought and reason to conclude these laws that are used to drive societal mores. These mores grow into cultural contextual presuppositions and preunderstanding that underwrite the moral laws in each society. “People know many things by acquaintance or intuition: their own mental states (thoughts, feelings, sensations), physical objects with which they are acquainted by the five senses, and, some would argue, basic principles of mathematics.” Both philosophers and theologians can agree with this premise. However, without a moral lawgiver (God) none of these conclusions could be met. Every law has a giver, and there is a moral law, therefore, a moral lawgiver is a natural conclusion that could reasonably be made.
If God is the creator of the heavens and earth (Genesis 1:1) and also created man in His image (Genesis 1:26), and man is the consumer and vehicle by which reason propels itself then God is the progenitor and center of all reason and wisdom in the universe. It is from God that humanity gets truth, wisdom, and all reason.
There is a great example of God’s reasoning with His divine counsel and later humanity in the book of Job. Most people use this beloved book to showcase many Christian principles but almost everyone fails to realize the overarching narrative of the story. The undertone of the book of Job is God’s reasoning with His creation.
The book of Job opens on a courtroom-like scenario that most people miss or overlook. Michael Heiser writes: “The Hebrew (Satan) means something like ‘adversary,’ ‘prosecutor’ or ‘challenger.’ It speaks of an official legal function within a ruling body – in this case, Yahweh’s council.” God is reasoning with Satan that Job, His faithful servant, will stay faithful and is worthy. From there the book enters into a long dialogue with Job, now stricken with disease, famine, and loss, with a small cohort of friends that try to reason with him on various theological levels. These dialogues postulate God’s sovereignty, Job’s sin, grace, etc. While most Christians are lost in the minutia of the poetry, the overriding vehicle by which this book propels itself is reason. Toward the end of the story, Job’s frustration demands an audience with God. This is such a telling portion of the story where God gives Job a diatribe, what can only be called Yahweh’s apologia for His creation, His laws, His purposes, His reason, etc. It illustrated how ignorant mankind is in the presence of God’s omniscience.
Doctrinal – Old Testament
The Old Testament has many incidents where prophets, speaking on behalf of God, actually instruct Israel to worship with a reasonable faith. One of the most poignant instances of this is Deuteronomy six, verses four through verse seven: “Hear, O Israel: The Lord our God, the Lord is one. You shall love the Lord your God with all your heart and with all your soul and with all your might” (Deuteronomy 6:4-5). Most Christians (and Jews for that matter) are familiar with this popular passage; however, its meaning has much more under the surface.
The reader needs to ask exactly what God is commanding His people to do. It is more than just hyperbole. “The soul is a substantial, unified reality that informs its body. The soul is to the body what God is to space — it is fully ‘present’ at each point within the body.” Humans use the mind to love and worship God and this involves the entire self, all its faculties, and all its capacities. Moreover, the Hebrew reiterates this: “with all of your heart and with all of your soul: The Hebrew terms levav (often translated ‘heart’) and nephesh (often translated ‘soul’) do not refer to separate components of the human person. Rather, the terms overlap in meaning, conveying the internal life, dispositions, emotions, and intellect.” Believers are never asked to separate their intellect from their feelings. True biblical love is a choice and one can never make a choice absent from the mind. Having faith in God can never be truly sincere and obedient without the use of reason within that faith.
Old Testament Epistemology
The Old Testament is replete with faith and reasonable epistemology. Epistemology is “the philosophical discipline which examines the nature and validity of human cognition.” Otherwise, stated, how do humans know things? The Old Testament extolled these truths long before Greek philosophy ever came onto the scene. Ancient Israel was propagating wisdom, love, theology, and reason centuries before Socrates was even born.
The entire book of proverbs is based on reasonable divine wisdom; Proverbs three is a wonderful example of this that also has moorings from the Deuteronomy exaltation. While the Proverbs deals with wisdom and reason and show the faithful how to believe and behave, the Psalms give a keen insight into why someone should believe. They point to the Glory and majesty of the Lord and speak of His omnipotence (Psalms 147:5), His omniscience (Psalm 139), His omnipresence (Psalm 11:4), His omnibenevolence (Psalm 31:19), and so much more. Moreover, Ecclesiastes (written by Solomon “the wise”) is an exposition on the folly of man in light of the glory of the Lord and His providential truth; it “is a book of wisdom sayings that examines the meaning of life’s endeavors, the value of common wisdom, and the problem of injustice.”
Job and Song of Songs also encompass wisdom literature of the Old Testament that gel faith and reason in worship and obedience. Wisdom is, after all, the pinnacle of a reasonable faith represented by obedience to the Lord for His glory in sacrificial worship.
Jesus is The God of Reason – New Testament
The New Testament is the most interesting of the two books in light of faith and reason. Not only were the New Testament writers and Jesus Christ alive during a precarious time for reason and faith in the world, but they were precisely in the right place at the right time in history for the creation and spread of Christianity. The middle east was a hotbed of philosophical thought and the birthplace of Greek philosophy. This is why the New Testament is steeped in such apologetical prose. It is from this worldview that Jesus Christ arrives and introduces the kingdom of God on earth available to all. It is from here that reasonable faith takes on a whole new meaning.
Jesus as The Logos
First and foremost, it would be a mistake to ignore the Greek use of the word Logos concerning Jesus. Like the aforementioned importance of definitions, here too it is vital that a foundational understanding of ancient Greek (the language of the New Testament) and its relevance to Jesus Christ. “Logos (λόγος, logos). A concept-word in the Bible symbolic of the nature and function of Jesus Christ. Also used to refer to the revelation of God in the world.” This is best showcased in the Gospel of John: “In the beginning was the Word, and the Word was with God, and the Word was God” (John 1:1). This is one of the most famous passages in the New Testament that shows the divinity of Christ. In the original Greek:
The word Logos (λόγος) is specifically used three times in this verse to emphasize who Christ was and what that relationship was to God the creator of all. “The word λόγος (logos) evolved from a primarily mathematical term to one identified with speech and rationality. At a basic level, logos means ‘to pick up, collect, count up, give an account [in a bookkeeping sense]’—the act of bringing concrete items into relation with one another.” In other words, Logos became synonymous with the term reason itself; “the Greek word logos comes from legō (‘I say’). logos means “word, speech, explanation, principle, or reason.” Just as was illustrated above with God as the outflowing of all the laws of creation and the universe, Jesus Christ early on was identified as not only the creator of all things in John 1:1 but, Jesus Christ was identified as the embodiment of rationality. All truth, faith, and reason flow from him, through him, and to him (Romans 11:36).
Doctrinal – New Testament
Jesus Christ repeats His father’s exhortation in Deuteronomy in the New Testament. Three different Gospels record this same doctrinal staple that was commanded to the Israelites centuries before. Three different accounts of this event are recorded in Matthew 22:37-40, Mark 12:30-31, and Luke 10:27. In all three accounts, the same sort of language and grammar is used to restate the great commandment that transcends all the other commandments. This is an emphatical admonition of the Christians that faith means obedience with the heart, mind, and body.
The New Testament is the personification of reason and faith. One could argue that every book in the New Testament has at least one element of faith and reason representative of the Christian way of life. From Jesus Christ’s sermon on the mount to His crucifixion defense (“And Jesus said, ‘I am, and you will see the Son of Man seated at the right hand of Power, and coming with the clouds of heaven’” [Mark 14:62]) and all through the epistles, there are ample examples of where and how Christ and His apostles instruct believers to use their minds in response to their faith. One of the best examples of this can be found in the book of Romans.
The apostle Paul wrote the book of Romans during his third missionary journey while he was in Greece (Acts 20:3), most likely from the Church of Corinth. Paul was a masterful apologist who spent much of his time defending the faith in controversial areas against eastern philosophical leadership. In this letter he makes a profound exhortation: “I appeal to you, therefore, brothers, by the mercies of God, to present your bodies as a living sacrifice, holy and acceptable to God, which is your spiritual worship. Do not be conformed to this world, but be transformed by the renewal of your mind, that by testing you may discern what is the will of God, what is good and acceptable and perfect” (Romans 12:1-2). The two verses intertwine faith and reason. It is out of faith that we offer the Christian body up in sacrificial worship; “Paul reminds us that we should offer our bodies to God because this is the most reasonable way to express service to Him in light of His mercies toward us.” This passage is a battle cry for the Christian community in Rome not to allow secular influences of the world to conform them to pagan ways but to use their intellect in the body of Christ (the Christian Roman Church) to test what is good and acceptable according to the will of God. J. P. Moreland laments; “Paul’s teaching about the centrality of the intellect for spiritual renewal was not new. The Old Testament is pregnant with this same idea in its teaching about the nature and role of wisdom in life.” This passage once again echoes the teachings of the shema (Deut. 6:4-5) that was covered above.
New Testament Epistemology
Much like the Old Testament, the New Testament is abounding with wisdom literature (in the form of epistles) that speak of faith carried out in rational and logical obedience to the word of God. The book of acts, more than any other shows how reason is used in the defense, admonition, and promulgation of the faith. Examples can be found in Acts 9:29; 14:1; 17:2; 19:8-9; 20:21; 28:23; and many others. Reason can be found in connection with faith in 1 Corinthians 13:11, 1 Peter 3:15, Hebrews 13:4, Philippians 4:8, and so much more.
Moreover, the New Testament authors speak against the concept of blind faith. In several instances, the authors encourage believers to be reasonably skeptical of what is being taught to them in their faith-based communities. Blind faith is unreasonable and an affront to sound worship. Apostles instructed Christians to test the spirits and beware of false prophets; it is reasonable to be a healthy skeptic in the search for sound theology. Critical thinking is a New Testament tool for discernment; see 1 John 4:1; 1 Thessalonians 5:21; Matthew 7:15.
The theme of using the mind, the body, and the soul to worship God and live a morally obedient life in accordance with the scriptures is personified in the New Testament. Both Testaments testify to the theme that blind faith and faith void of intellectual prowess is both antithetical to biblical faith but could, and did, drive people out of the faith.
Synthesis – Faith Seeking Understanding
There is a final point that needs to be made which can synthesize the faith and reason amalgamation. What is commonly misunderstood is that reason does not generate faith. Reason can lead the lost to the door but will not open it. This is clear in both Church history and scripture. Faith seeks understanding but understanding never causes genuine faith, this is a massive misconception in apologetic circles.
The scriptures are clear that regeneration (conversion to Christ) is an act of God’s grace and mercy; He does the work, not human will: “For by grace you have been saved through faith. And this is not your own doing; it is the gift of God, not a result of works, so that no one may boast” (Ephesians 2:8-9). This is the word of the Holy Spirit (Titus 3:5). Therefore, “faith comes from hearing, and hearing through the word of Christ” (Roman 10:17). This is why preachers preach, evangelists evangelize, and apologists defend. Reason alone cannot lead someone to rebirth but what it does is combat bad theology, defend the faith, and intrigue the lost. St. Augustine of Hippo wrote about this which was later championed by the great Thomas Aquinas. This has been a mainstay of Church dogma since the patristic age.
What conclusions can believers draw from this? Reason makes faith more understandable and applicable to the life of discipleship. What becomes of the disciple is a faith that seeks understanding in the ways and life of Jesus Christ. “Christian faith and right reason move in a dynamic interplay, drawing upon several. disciplines, with the goal of wisdom, understanding, and knowledge—all part of our general discipleship in Christ, the Wisdom of God.” This is a brilliant model for understanding faith and reason without getting lost or discouraged in argumentative or contemplative grandiloquence.
The faith-seeking understanding approach to the Christian way of life has two power dynamics that demarcate the method. The first foundation is rooted in biblical faith which focuses on discipleship of the human intellect in search of higher wisdom and understanding of God, creation, and ourselves. The second pillar of faith seeking understanding is an honest reflection upon Christian theology in use and practice from the perspective of critical, philosophical, and scientific reason. These two foundational pillars promote the transformation of the mind with a high view of God rooted in sound biblical Christology.
Reason aides and undergirds true biblical Christianity. Reason serves as a healthy counterbalance to faith and Christians use reason to better understand sound theology and healthy religious dogma. Old Testament theology and New Testament theology co-exist to synthesize timeless discipleship that supports reasonable faith. Finally, faith in search of appropriate understanding can better serve God in His kingdom with obedient worship, reasonable faith, and to His immaculate glory.
Barry, John D., David Bomar, Derek R. Brown, Rachel Klippenstein, Douglas Mangum, Elliot Ritzema, Carrie Sinclair Wolcott, Lazarus Wentz, and Wendy Widder. “Lexham Bible Dictionary.” Lexham Press, January 1, 2016. https://lexhampress.com/product/36564/lexham-bible-dictionary.
Barry, John D., ed. NIV Faithlife Study Bible: Intriguing Insights to Inform Your Faith. Bellingham, WA: Lexham Press, 2012.
Brannan, Rick. Lexham Research Lexicon of the Greek New Testament. Bellingham, WA: Lexham Research Lexicons, 2020.
Craig, William Lane. Reasonable Faith: Christian Truth and Apologetics. Wheaton, IL: Crossway Books, 2008.
Evans, C. Stephen. Pocket Dictionary of Apologetics & Philosophy of Religion. Downers Grove, IL: InterVarsity Press, 2002.
Geisler, Norman L. Baker Encyclopedia of Christian Apologetics. Grand Rapids, MI: Baker Books, 1999.
Geisler, Norman L., and Frank Turek. I Don’t Have Enough Faith to Be an Atheist. Wheaton, IL: Crossway Books, 2007.
Heiser, Michael S. The Unseen Realm: Recovering the Supernatural Worldview of the Bible. Bellingham, WA: Lexham Press, 2015.
Lewis, C. S. Mere Christianity. New Jersey, NJ: Barbour and Company, 1952.
Livingstone, Elizabeth A., and F. L. Cross, eds. The Concise Oxford Dictionary of the Christian Church. Oxford, NY: Oxford University Press, 2005.
Moreland, James Porter, and William Lane Craig. Philosophical Foundations for a Christian Worldview. 2nd ed. Downers Grove, IL: InterVarsity Press, 2017.
Moreland, James Porter. Love Your God with All Your Mind: The Role of Reason in the Life of the Soul. Colorado Springs, CO: NavPress, 2012.
Walvoord, John F., and Roy B. Zuck. The Bible Knowledge Commentary. Wheaton, IL: Victor Books, 1985.
Wilkens, Steve, Craig A. Boyd, Alan G. Padgett, and Carl A. Raschke. Faith and Reason: Three Views. Spectrum Multiview Book Series. Downers Grove, IL: InterVarsity Press, 2014.
 James Porter Moreland and William Lane Craig, Philosophical Foundations for a Christian Worldview, 2nd ed. (Downers Grove, IL: InterVarsity Press, 2017), 16.
 William Lane. Craig, Reasonable Faith: Christian Truth and Apologetics (Wheaton, IL: Crossway Books, 2008), 24.
 Unless otherwise noted, all scripture is taken from The Holy Bible: English Standard Version.
 Moreland, Craig, Philosophical Foundations, 19.
 C. Stephen Evans, Pocket Dictionary of Apologetics & Philosophy of Religion (Downers Grove, IL: InterVarsity Press, 2002), 99.
 For more on this look for The God Delusion by Richard Dawkins and God is not Great by Christopher Hitchens, both books postulate this perspective in detail and with specific examples.
 C. S. Lewis, Mere Christianity (New Jersey, NJ: Barbour and Company, 1952), 4.
 Moreland, Craig, Philosophical Foundations, 62.
 Norman L. Geisler and Frank Turek, I Don’t Have Enough Faith to Be an Atheist (Wheaton, IL: Crossway Books, 2007), 171.
 Michael S. Heiser, The Unseen Realm: Recovering the Supernatural Worldview of the Bible (Bellingham, WA: Lexham Press, 2015), 56-57.
 James Porter Moreland, Love Your God with All Your Mind: the Role of Reason in the Life of the Soul (Coloradp Springs, CO: NavPress, 2012), 81.
Rick Brannan, ed., Lexham Research Lexicon of the Greek New Testament, Lexham Research Lexicons (Bellingham, WA: Lexham Press, 2020).
 Moreland, Love Your God, 76.
 Ibid, 77.
Steve Wilkens et al., Faith and Reason: Three Views (Downers Grove, IL: InterVarsity Press, 2014), 86.
 Ibid, 86.
 Ibid, 86.