Sola Scriptura Explained: What It Means, Biblical Evidence, and Why It Matters

Among the five solas of the Protestant Reformation, sola scriptura is one of the most foundational—and, in my experience, one of the most misunderstood.

Many Protestants affirm the authority of the Bible without fully considering what that means for the authority of church traditions, denominational teachings, personal experiences, and even their own interpretations. What happens when these sources of authority appear to conflict? Which one ultimately determines what Christians ought to believe?

These questions were central to Part 1 of my debate with Roman Catholic historian Dr. Ed Mazza, in which we spent approximately two hours discussing biblical authority and sola scriptura (click HERE to watch the full debate).

However, sola scriptura is about far more than the Protestant-Catholic debate. It is a doctrine that should shape how every Protestant approaches Scripture, evaluates theological claims, and lives out the Christian faith.

In this article, I want to answer three questions: What is sola scriptura? What is the biblical evidence for it? And, importantly, what does it protect Protestants from?

My argument is that sola scriptura establishes Scripture as the church’s final infallible rule for faith and practice. Properly understood, it protects us from elevating human traditions, private interpretations, or personal experiences above God’s revealed Word—without requiring us to reject the wisdom and authority God has given to the church.

What Is Sola Scriptura?

Sola Scriptura is not "solo" scriptura. Read that again.

The doctrine of sola scriptura does not teach that Scripture (the Bible) is the only authority. This is a common misconception of the doctrine.

Rather, sola scriptura teaches that Scripture is the sole infallible rule of faith and practice for the church. In other words, Scripture is the final authority against which all other claims about Christian faith and practice must be evaluated.

Protestants can and should acknowledge other sources of authority, such as church elders, tradition, creeds, church councils, and the early church fathers. These sources can provide genuine authority and valuable guidance. Where Protestants differ from Roman Catholics and Eastern Orthodox Christians is that we do not recognize these sources as possessing the same status as Scripture: their teachings must remain accountable to the written Word of God.

Before moving on too quickly, it is important to define our terms. By infallible, I mean that something cannot err. Fallibility, on the other hand, means that something can err, but not necessarily that it always does. Fallible sources of authority can be correct, and often are, but the possibility of error remains.

This distinction is important because affirming the authority of Scripture does not mean that all who affirm sola scriptura must agree on everything. While Scripture is infallible, we are not. It is difficult to find anything about which all human beings agree. This disagreement does not, by itself, demonstrate a problem with Scripture’s authority. Rather, it highlights our limited psychological state as fallible, fallen human beings.

We are fallible subjects attempting to understand what an infallible source of authority teaches. We can misunderstand a passage, overlook its context, or bring our own assumptions to the text. The fact that people disagree about Scripture does not mean that Scripture itself is unclear on every disputed matter, nor does it mean that all interpretations are equally valid.

Oftentimes, Roman Catholics will argue that it is problematic for Protestants to interpret the Bible “however they want” and that an infallible text requires an infallible interpreter.

To keep it brief (you can watch my full response to this in Part 1 of my debate on this topic HERE), the existence of an authoritative interpreter does not eliminate the need for interpretation.

Catholics distinguish between the authority of the Church’s teaching office, or Magisterium, and an individual’s interpretation of its teachings. However, Catholics must still identify which teachings have been infallibly defined, determine the scope of those definitions, and interpret what they mean.

This does not mean the two positions are identical, but it does show that appealing to an infallible interpreter does not automatically eliminate every difficulty associated with interpretation.

Despite our limitations, we are made in the image of a rational God and are capable of knowing Him. God has also given us other sources of authority, including pastors and teachers, to assist us in understanding His Word (Eph. 4:11–16). Furthermore, Scripture itself communicates many essential truths clearly, even if not every passage or doctrine is equally easy to understand prima facie. It can be said like this, “the main things are the plain things.” 

Having addressed what sola scriptura is and what it is not, we can now consider the case for the doctrine.

The Evidence for Sola Scriptura

The argument for sola Scriptura can be developed by considering two related claims: the unique authority of Scripture and its self-sufficiency for faith and practice.

First, Scripture possesses a unique authority because it is God’s inspired Word. Second, Scripture is sufficient to serve as the church’s final infallible rule without requiring another infallible rule alongside it.

These claims are related, but they are not identical. The fact that God cannot err establishes the infallibility of His Word. The further claim that Scripture is the sole infallible rule requires us to consider what Scripture teaches about its own authority and sufficiency.

Let’s begin with the unique authority of Scripture.

The Unique Authority of Scripture

Scripture is infallible because it is God’s Word. Roman Catholics and Protestants alike affirm that God is truthful and cannot lie. As Titus 1:2 says, God never lies, and Hebrews 6:18 similarly teaches that it is impossible for God to lie.

Therefore, because Scripture is God’s inspired Word, it carries His authority and is trustworthy in what it teaches. But why does this matter for sola scriptura?

Because Scripture’s divine origin distinguishes it from other sources of authority. Pastors, church councils, theologians, traditions, and even the early church fathers may communicate truth, but their teachings are not thereby placed on the same level as God’s inspired Word. I like what Gavin Ortlund said on this point: 

“Just as the Bible is unique in its nature, so it is correspondingly unique in its authority…why accept what isn’t the speech of God to have comparable infallibility to that which is the speech of God?”[1]

The point is not that God cannot communicate truth through other means. Rather, it is that we must distinguish God’s inspired revelation from the fallible human transmission, interpretation, and application of that revelation.

Scripture is therefore unique in its authority because it is God’s inspired Word. This provides the foundation for recognizing Scripture as the church’s final infallible rule.

Biblical Evidence for the Sufficiency of Scripture

Moreover, the Bible teaches that Scripture is sufficient to equip believers for faith and practice. Namely, no additional infallible rule alongside Scripture is necessary.

This is not to say that other sources of authority are unnecessary. As discussed above, God has given us pastors, teachers, and the wider church to help us understand and apply His Word. The question is whether we need another infallible rule of faith alongside Scripture.

Consider the following passages.

2 Timothy 3:14–17

“But as for you, continue in what you have learned and have firmly believed, knowing from whom you learned it and how from childhood you have been acquainted with the sacred writings, which are able to make you wise for salvation through faith in Christ Jesus. All Scripture is breathed out by God and profitable for teaching, for reproof, for correction, and for training in righteousness, that the man of God may be complete, equipped for every good work.” (1 Tim. 3:14-17)

This is one of the most important passages for understanding the sufficiency of Scripture.

Paul teaches that Scripture is “breathed out by God” and is profitable for teaching, reproof, correction, and training in righteousness. Its purpose is to equip the servant of God for every good work.

This is more than an affirmation that Scripture is useful. Paul describes it as capable of equipping God’s servant for the work God has called him to do.

If Scripture is sufficient to equip believers for every good work, why would we need another infallible rule alongside it? The passage provides strong support for the sufficiency of Scripture, even though the further conclusion that no other infallible rule is necessary requires considering the broader biblical argument.

Importantly, the immediate context refers to the sacred writings Timothy had known from childhood, primarily the Old Testament. This does not mean the New Testament is excluded from Scripture. Other passages recognize New Testament writings as Scripture as well. For example, 1 Timothy 5:18 places a saying from Luke 10:7 alongside a quotation from Deuteronomy, while 2 Peter 3:15–16 refers to Paul’s letters in connection with “the other Scriptures.”

Thus, the New Testament itself provides grounds for recognizing the apostolic writings as Scripture.

Acts 17:11

“Now these Jews were more noble than those in Thessalonica; they received the word with all eagerness, examining the Scriptures daily to see if these things were so.” (Acts 17:11 ESV)

The Bereans received Paul’s proclamation eagerly but also examined the Scriptures daily to determine whether what he and Silas were teaching was true.

Notice that they did not simply accept the message without examination because of the authority of those proclaiming it. Instead, they evaluated the proclamation in light of the Scriptures.

This is an important principle for Christians today. Even when we respect the authority of pastors, teachers, and Christian scholars, we should examine their teaching against God’s Word.

The passage does not mean that the Bereans rejected every other source of authority.

Rather, it illustrates the importance of testing teaching against the Scriptures. If even apostolic proclamation was examined in light of the Scriptures available to the Bereans, we have good reason to evaluate the claims of later teachers and traditions against God’s revealed Word.

John 20:30–31

“Now Jesus did many other signs in the presence of the disciples, which are not written in this book; but these are written so that you may believe that Jesus is the Christ, the Son of God, and that by believing you may have life in his name.” (John 20:30-31 ESV)

John explicitly states the purpose of his Gospel: that readers may believe Jesus is the Christ, the Son of God, and have life in His name.

This demonstrates the power of the written testimony concerning Jesus to bring people to saving faith. John does not suggest that readers must first obtain another infallible interpretation of his account before they can believe.

Of course, this passage does not independently establish that the entire biblical canon is sufficient for every question of faith and practice. However, it supports the broader point that the written Word is capable of communicating the truth about Christ and leading people to life in His name.

Matthew 15:1–9 and Mark 7:1–13

“Then Pharisees and scribes came to Jesus from Jerusalem and said, 'Why do your disciples break the tradition of the elders? For they do not wash their hands when they eat.” He answered them, “And why do you break the commandment of God for the sake of your tradition? For God commanded, ‘Honor your father and your mother,’ and, ‘Whoever reviles father or mother must surely die.’ But you say, ‘If anyone tells his father or his mother, “What you would have gained from me is given to God,” he need not honor his father.’ So for the sake of your tradition you have made void the word of God. You hypocrites! Well did Isaiah prophesy of you, when he said: “‘This people honors me with their lips, but their heart is far from me; in vain do they worship me, teaching as doctrines the commandments of men.’” (Matt. 15:1-9 ESV, emphasis added)

In this passage, Jesus condemned human traditions (commandments of men) that displaced or undermined God’s commandments, illustrating the incompatibility between Scripture and competing infallible authorities. 

Jesus’ criticism establishes an important principle: tradition must never be permitted to override, undermine, or nullify God’s revealed commands.

One might object that Jesus was condemning merely human traditions, not traditions that are genuinely divine. Catholics, for example, distinguish apostolic tradition from merely human customs.

But how can anybody know they are merely “human” traditions? Elsewhere, Jesus affirmed that the Pharisees had God-given authority to teach God’s people (Matt. 23:2-3). Moreover, the Pharisees themselves didn’t view their traditions as merely human but passed down from Moses through God’s commandments given to him. The Pharisees viewed their traditions as, according to D.A. Carson, “having authority very nearly equal to the canon.”

That is an important distinction, and Matthew 15 does not, by itself, settle the entire debate over apostolic tradition. However, it raises a fundamental question: How do we determine whether a tradition genuinely reflects God’s revelation or instead undermines it?

Protestants argue that Scripture provides the final infallible standard by which such claims must be evaluated. A tradition’s claim to divine origin cannot, by itself, establish that it possesses divine authority.

This is similar to the concern Jesus addresses in Mark 7:13, where He says that the Pharisees were “making void the word of God by your tradition that you have handed down.” His concern was not simply that one isolated tradition was mistaken, but that their traditions could undermine God’s commandments.

The lesson is not that every tradition is wrong. Rather, traditions must remain accountable to God’s revealed Word.

1 Corinthians 4:6

“I have applied all these things to myself and Apollos for your benefit, brothers, that you may learn by us not to go beyond what is written, that none of you may be puffed up in favor of one against another.” (1 Cor. ‭4‬:‭6‬ ‭ESV, emphasis added‬)

Paul writes that the Corinthians should learn “not to go beyond what is written.” This verse is sometimes appealed to in support of sola scriptura. Although interpreters debate the precise referent of “what is written” in this passage, Paul’s instruction is consistent with the broader principle that human claims should not be elevated above God’s revelation.

I would not rest the entire case for sola scriptura on this verse alone. Instead, it serves as a supporting consideration alongside the clearer teaching concerning Scripture’s inspiration, authority, and sufficiency.

Taken together, these passages support the Protestant conviction that Scripture is God’s inspired Word, sufficient to equip His people, and the final infallible standard against which other claims about faith and practice must be evaluated.

The case for sola scriptura is therefore not that every other source of authority is useless or wrong. Rather, it is that no other continuing source of authority should be placed alongside Scripture as an equally infallible rule for the church.

Having established the biblical foundation for the doctrine, we can now consider why it matters so much for Protestants.

The Shield: What Sola Scriptura Protects Us From

Sola Scriptura is not merely a doctrine that Protestants hold and Catholics deny. It is foundational to how Protestants should approach the Christian faith. It is also a shield, protecting us from dangers that are easy to fall into. In particular, I want to consider three: traditionalism, individualism, and experientialism.

1. Traditionalism

The first danger is traditionalism.

By holding Scripture as the final infallible rule, we recognize that all other traditions must remain accountable to its teaching. This is the lesson illustrated by the Bereans and the Pharisees, as discussed above. Church traditions, denominational distinctives, and established practices must all be evaluated in light of God’s Word.

This is a common point of disagreement between Catholics and Protestants. The Catholic Church recognizes Sacred Tradition alongside Scripture as part of the transmission of divine revelation, with the Magisterium serving the deposit of faith. Protestants who affirm sola scriptura reject the claim that a continuing body of extra-biblical tradition constitutes another infallible rule of faith.

The concern is that teachings which cannot be established from Scripture may nevertheless be imposed on believers as binding articles of faith.

This is a common point of disagreement between Catholics and Protestants. For Catholics, the Church views church tradition as another source of infallible authority on par with Scripture. However, as I mentioned in my debate with Dr. Ed Mazza, this inevitably leads to traditions being bound to the conscience of believers, which is burdensome. 

This is especially the case for said traditions that are dogmatically proclaimed infallibly by the Catholic Church that are not clearly taught in Scripture. This includes at least the following: the immaculate conception of Mary, her bodily assumption, the veneration of Mary and other saints, prayers to Mary and the saints, the infallibility of the pope, the existence of purgatory, the inspiration and canonicity of the Acrophya, the doctrine of transubstantiation, the worship of the transformed Host, the special sacerdotal powers of the Roman Catholic priesthood, and the necessity of works to obtain eternal life. 

These all have been proclaimed as infallible dogma by the Catholic Church, meaning they are binding on the conscience of all Catholics. However, this flies in the face of what Protestants hold when it comes to salvation: that we are saved by faith alone in Christ alone. This is explicitly taught in Scripture (see part 2 of my debate on salvation with Dr. Ed Mazza for my defense of this position HERE). 

With this being said, Protestants are not off the hook.

While we may not always elevate traditions to the same level as the Catholic Church does, we too often elevate man-made traditions. 

Confessions of faith, for example, can be good and even necessary for churches to establish their doctrinal commitments. They can help clarify what a church believes and provide accountability for its teachers. But they can also be abused.

Consider a church that requires all members to affirm either a young-earth or an old-earth position as a condition of membership, even though this is not a primary binding issue on Christians, not being clearly taught in Scripture. Christians can and should discuss the age of the earth, but we ought to be careful about making disputed interpretations a test of Christian faithfulness.

The same applies to church customs, such as dress codes. There is nothing inherently wrong with a church establishing certain practices for its community. The problem arises when a preference or custom is treated as though God Himself has commanded it.

There is a fine line between saying, “This is just the way we do things around here,” and saying, “This is what God requires of you.” Sola Scriptura helps us recognize that distinction. As Dr. Michael Krueger puts it, “Nobody gets to bind your conscience other than God.”[2]

Of course, God can bind our consciences through His revealed Word, and church leaders can rightly teach and apply that Word. The point is that no human authority has the right to turn its own preferences into divine commands.

2. Individualism

The second danger is individualism.

This is a prominent problem among Protestants and one that Catholics rightly criticize when they encounter it. The idea is that all you need is yourself and your Bible. No other source of authority or wisdom is necessary. You simply read the Bible for yourself and draw your own conclusions.

But what you really have in that situation is your own interpretation of the Bible. The authority of Scripture is not identical to the correctness of your interpretation of Scripture.

You can affirm that the Bible is infallible while misunderstanding what it teaches. Your confidence in an interpretation does not make that interpretation correct. This is why we should seek to understand Scripture in community, under the guidance of pastors and teachers, and with the benefit of Christian scholarship and church history.

Again, sola scriptura does not mean "solo" scriptura. We do not mean that Scripture is the only authority, but that it is the only infallible rule of faith and practice. God has given the church pastors and teachers for a reason. Ephesians 4:11–14 says:

“And he gave the apostles, the prophets, the evangelists, the shepherds and teachers, to equip the saints for the work of ministry, for building up the body of Christ, until we all attain to the unity of the faith and of the knowledge of the Son of God, to mature manhood, to the measure of the stature of the fullness of Christ, so that we may no longer be children, tossed to and fro by the waves and carried about by every wind of doctrine, by human cunning, by craftiness in deceitful schemes.” (Eph. 4:11-14 ESV)

God has given the church teachers to equip believers and help them grow in maturity. We should therefore be willing to learn from those who have studied Scripture deeply, including pastors, theologians, scholars, and faithful Christians who have gone before us.

This does not mean that these individuals are infallible or that we must accept everything they teach. Rather, it means we should wisely use the gifts God has given His church. It is also important for believers to study Scripture together and hold one another accountable. Continuing in Ephesians 4:15–16, Paul writes:

“Rather, speaking the truth in love, we are to grow up in every way into him who is the head, into Christ, from whom the whole body, joined and held together by every joint with which it is equipped, when each part is working properly, makes the body grow so that it builds itself up in love.” (Eph. 4:15-16 ESV)

Christian growth is not meant to take place in isolation. We are members of Christ’s body, and we need one another. Sola Scriptura should therefore encourage humility, not individualism. Because Scripture is infallible and our interpretations are not, we should be willing to have our conclusions challenged and corrected by other believers.

We should not be satisfied merely because we have arrived at an interpretation that makes sense to us. Instead, we should diligently seek to understand the intended meaning of the biblical authors, considering the historical context, the broader biblical teaching, and the insights of the wider church.

3. Experientialism: When Experience Becomes the Final Authority

There is another danger worth discussing, and that is experientialism.

This occurs when someone elevates personal experiences, feelings, or perceived revelations above Scripture. For example, someone might claim that God has told them something and then treat that impression as authoritative even when it contradicts what Scripture teaches (or maybe they never even decided to check it against what is taught in Scripture).

The problem is not that Christians have experiences with God. We can and should expect a personal relationship with the living God. The problem arises when our experiences become the highest authority by which we judge what is true.

Why should we trust every feeling or impression we have? We are fallible. We can misunderstand our emotions, mistake our desires for divine guidance, or misinterpret the circumstances around us. Sincerity and confidence do not guarantee that we are correct.

Perhaps we feel strongly that God is leading us in a particular direction. That feeling may be worth considering, but it does not follow that the feeling itself is infallible. We must be willing to test our impressions rather than simply assume that they come from God.

God cannot lie or contradict His own truth (Titus 1:2; Heb. 6:18). Therefore, if an apparent revelation genuinely contradicts God’s Word, we have reason to reject the claim that it came from Him. We should also consider whether we have misunderstood either the biblical passage or the experience itself.

This is another reason sola scriptura matters. Our feelings are not the final authority, nor are our personal experiences beyond scrutiny. Everything we believe God has revealed must be evaluated in light of what He has already revealed in Scripture.

This does not mean that God is distant, that prayer is meaningless, or that Christians should ignore the work of the Holy Spirit in their lives. Rather, it means that we should never elevate our subjective experiences above God’s infallible Word.

Conclusion: Holding Fast to God’s Word

Sola Scriptura is not merely a doctrine to defend in debates with Roman Catholics. It is a foundational principle that should shape the faith and practice of every Protestant Christian.

It guards us against traditionalism by reminding us that no human tradition can override God’s revealed Word.

It guards us against individualism by reminding us that our interpretations are fallible and that we need the wisdom and correction of the wider church. And it guards us against experientialism by reminding us that our feelings and personal impressions must never take precedence over what God has revealed.

But sola scriptura is not a rejection of the church, Christian tradition, scholarship, or the work of the Holy Spirit. Rather, it gives us a framework for rightly understanding their roles. We should listen to pastors, learn from church history, study alongside fellow believers, and remain open to correction—all while recognizing Scripture as our final infallible standard.

Ultimately, sola scriptura should produce neither arrogance nor isolation, but humility and confidence: humility because our interpretations can be mistaken, and confidence because God has spoken.

We have been given the Scriptures as a gift from our gracious God. Let us therefore study them diligently, interpret them carefully, learn from the church faithfully, and submit ourselves to their teaching wholeheartedly. Our final authority is not what we prefer, what we feel, or what has always been done, but what God has revealed in His Word.

May we treasure that gift and remain steadfast in the truth of the living God, who has given us a living hope through the resurrection of Jesus Christ (1 Peter 1:3).

Footnotes

[1] Gavin Ortlund, “Gavin Ortlund Vs. Trent Horn: Is Sola Scriptura True,” Pints With Aquinas, March 3, 2023, debate video, 19:17, https://www.youtube.com/watch?v=kn7qdPSHSJk.

[2] Michael Krueger, “The Case for Sola Scriptura You Probably Haven’t Heard (Michael Kruger),” The Sean McDowell Show, October 2, 2026, 20:30, https://youtu.be/vOtMTh0pxAU?si=2gOwZ-1lOIMchzfO.