Scripture Alone

Jeremiah 17:9-10

“The heart is deceitful above all things, and desperately sick; who can understand it?
‘I the LORD search the heart and test the mind, to give every man according to his ways, according to the fruit of his deeds.’”

The doctrine of Scripture alone begins with a problem. Notice the question: “Who can understand it?” The prophet's rhetorical question confronts us with a difficult reality: we cannot. That truth can be uncomfortable because the heart is the very instrument we use to evaluate nearly everything else. Yet Scripture tells us that the instrument itself is unreliable. I have never met anyone who naturally assumes, “I am probably mistaken in the way I feel about matters.” The human heart does not arrive with hesitation or self-doubt. It arrives confident, convinced, and almost always certain that it is right.

John Calvin saw where this leads. In the Institutes he wrote that "the human heart (or mind) is, so to speak, a perpetual forge of idols." The heart does not merely err by accident. It manufactures false authorities, and it works overtime. Left to itself, it will build a god who agrees with us, a standard that flatters us, and a voice that says what we already wanted to hear.

Now consider verse 10. Who is the judge? "I the LORD search the heart." The verdict does not come from within us. It comes from outside us, from the One who knows us better than we know ourselves.

That is what we mean by sola scriptura. We do not mean that reason, evidence, experience, and the wisdom of godly teachers are worthless. We mean that they are servants, not sovereigns. Only Scripture is God-breathed, and therefore only Scripture stands as the final authority over the conscience of the believer. Every other source is judged by the authority of God’s Word, and never the reverse.

How We Came to Hold Scripture Alone: Trust Placed Elsewhere

Why did the Reformers need to recover the conviction of Sola Scriptura (Scripture Alone)? Because the church, like the heart, had drifted. When Luther nailed his theses to the door in 1517, the visible scandal was indulgences, a form of propheteering which offered forgiveness of sins at a price. But indulgences were only the fruit. The deeper issue was a shift in authority and trust. The church had gradually moved from resting upon God's Word to relying upon other voices equally alongside it.

In the medieval church, ecclesiastical office and tradition were gradually elevated alongside the Word of God, and eventually above it. The distinction between what God had spoken and what the church declared became increasingly blurred. Later, a different authority took the throne. Reason and the emerging sciences were employed not merely as tools to illuminate Scripture, but as judges set over it. Whatever the age deemed implausible was dismissed, and whatever the deceitful heart found useful was quietly smuggled in. In our own day, the seat of authority has shifted yet again, from the church and from reason to the self and the surrounding culture. "I feel," we say, "therefore it must be true."

Different centuries, the same error. Trust is placed in the church, in human intellect, or in shifting feelings rather than in the Word alone. The idol changes shape, but the heart remains the same. It is the same idol factory with new branding.

Into this world stepped William Tyndale, convinced that ordinary people should have the Bible in their own language. When told the common man was better off without it, he replied, as John Foxe records, “If God spare my life ... a boy that driveth the plough shall know more of the Scripture than thou dost.” Hunted across Europe, Tyndale was eventually martyred in 1536. His reported final prayer was, “Lord, open the King of England’s eyes.” And within just a few years, an English Bible stood in the churches of England. Tyndale gave his life so that ordinary believers could test every claim of priest and preacher by the Word of God for themselves.

The Biblical Warrant and the Unity of the Word

But is such trust warranted? Scripture answers with two clear witnesses. Paul writes that “All Scripture is breathed out by God” and is sufficient to teach, correct, and equip God’s people for every good work (2 Tim. 3:16-17). Because it comes from God, it is trustworthy and sufficient. Proverbs then warns of the alternative: “There is a way that seems right to a man, but its end is the way to death” (Prov. 14:12). Notice the phrase seems right. That is Jeremiah’s deceitful heart at work: sincere, confident, and tragically mistaken.

So, allow Jeremiah's question to press on us once more. If the heart is a factory of idols, could such a heart have produced this book? Consider what we actually hold: some forty authors, writing over roughly fifteen hundred years, in different lands, languages, and centuries, kings and shepherds and fishermen and a physician. Committees struggle to produce a consistent memo in one afternoon. Yet this library tells one story, and it points to one person.

Consider Joseph, hated by his brothers out of jealousy, plotted against, sold as a slave for silver, and then raised up to save the very men who betrayed him. Read that beside the Gospels, and you see the Son who came to His own and His own betrayed him for the price of a slave, yet who saves those who rejected Him.

Consider Moses, who represents the law. He leads the people to the edge of the land but cannot enter it. The law can bring you to the border, but it cannot bring you home. It is Joshua who leads Israel across the Jordan into rest, and Joshua's name is the same Hebrew form of the name Jesus. The New Testament itself draws the line in Hebrews 4: it is Jesus who gives the rest that Joshua only foreshadowed.

Consider the thread of blood that runs through the Scriptures. After Adam and Eve sinned, God clothed them with garments of skin, a covering that came at the cost of another life. At Passover, a lamb was slain, and its blood shielded God's people from judgment. Later, the tabernacle stood in the midst of Israel, covered with animal skins and filled with the continual reality of sacrifice, while the presence of God dwelt among His people. Then John the Baptist points to Jesus and declares, “Behold, the Lamb of God, who takes away the sin of the world.” And John tells us that the eternal Word became flesh and “dwelt” among us, literally, “tabernacled” among us. The garments, the lamb, and the tabernacle were never ends in themselves. They were signposts pointing forward to Christ. At the cross, their meaning is revealed and their purpose fulfilled.

A deceitful heart produces idols that flatter ourselves, excuse us, and place us at the center. It does not invent a message that exposes our guilt, strips away every claim of self-righteousness, and declares that our only hope is a crucified Messiah. Nor does it write a story in which salvation is received entirely by grace, apart from any achievement we can claim. The Bible's unifying message runs against the grain of fallen human nature. Its coherence across centuries, authors, and circumstances bears the unmistakable fingerprint of a single divine Author.

Trust the Word Alone: Pick It Up Today

So, what do we do with this? Trust Scripture alone.

Not men, no matter how gifted, beloved, or impressive their titles. Not even external evidences such as science or archaeology, as though God's Word required a higher authority to validate it — we instead measure them against the Word of God. Not our feelings, which Jeremiah has already taught us to distrust. And not even creeds and confessions. I say that as a Reformed Christian who deeply values them. Yet notice that faithful creeds are filled with Scripture references, and those references are not decorative footnotes. They are arrows pointing beyond themselves to the Word of God. A good creed is a signpost, and a signpost is never the destination. Scripture alone stands as the final authority for the believer.

Here is your step for this week: bring your questions to Scripture. Bring the teaching you have heard, the opinions you have absorbed, the doubts you have carried, and the convictions you have assumed. Do not settle for what sounds persuasive, what feels right, or what the crowd believes. Read good authors and trusted theologians, but always ask whether their conclusions are grounded in the Word of God. Test every claim against the authority of Scripture.

Take that question you have wrestled with for years and bring it before the only authority worthy of answering it. Open God's Word, search it with humility, and follow where it leads. When God speaks, submit to His Word. The goal is not merely to find answers, but to have our minds and hearts shaped by the One who cannot lie, cannot err, and has spoken.

And remember that this privilege came at a cost. William Tyndale crossed a continent in hiding and ultimately gave his life so that ordinary people could read the Scriptures in their own language. He wanted the boy behind the plow to have direct access to God's Word. Most of us have a Bible within arm's reach right now, perhaps several. One may even be on your phone. Honor that sacrifice. Open it. Read it. And let God speak for Himself.

With love in Christ,

Pastor Chris