Does It Matter What You Believe—As Long As You’re Sincere?
A Christian Response from Past and Present Theologians
🧩 Introduction: A Question of Sincerity
We live in a world that champions personal authenticity. “Follow your heart” is our cultural creed. So it’s not surprising that a popular belief today is this:
“It doesn’t matter what you believe as long as you’re sincere.”
Sounds kind, doesn’t it? It appeals to our longing for peace, tolerance, and unity. But here’s the problem: Is it true? More to the point—does sincerity save you?
Let’s take a deep dive into what past and present Christian leaders and theologians have said about this very idea. Because while sincerity is important, the Bible—and the great minds who’ve taught it—tell a much different story.
🎭 Sincerity Without Truth: A Misguided Compass
Imagine you’re hiking in the mountains (a familiar picture here in Odell and Pine Grove). You pull out a compass and confidently set off in the direction you believe leads home. You’re sincere. But if that compass is broken, you’re sincerely lost.
“You can be sincere and still be sincerely wrong.” — R.C. Sproul
Sincerity alone, without truth, doesn’t lead to safety. It doesn’t fix your compass.
🕰️ Voices from the Past: Early and Classical Theologians
✝️ Augustine of Hippo (354–430 A.D.)
Augustine was a North African bishop and one of the most influential Christian thinkers of all time. He warned that people often believe what they want to be true, not what is true.
“It is not by the merits of our will, but by the mercy of God, that we are saved… for even error can be held with passion.”
— Confessions
Augustine would say that a man can love error with all his heart and still miss salvation. Sincerity cannot correct falsehood.
🛐 Justin Martyr (100–165 A.D.)
As one of the first apologists of the Christian faith, Justin Martyr argued that only those who followed Christ could be rightly related to God. While he acknowledged that some pagan philosophers sought truth, he insisted their sincerity was not enough.
“Those who lived according to reason are Christians… yet those who lived in error, though sincere, did not know the Logos.”
— First Apology
Justin points out that seeking truth apart from Jesus—the Logos—isn’t salvific, no matter how heartfelt.
🪶 John Wesley (1703–1791)
The founder of Methodism emphasized the heart and holy living, but he did not claim all beliefs were equally valid. Wesley was generous toward other traditions, but he also stressed the importance of right doctrine.
“Orthodoxy or right opinion is at best a very slender part of religion… yet right belief is still important.”
— A Plain Account of Christian Perfection
Wesley welcomed many into the Christian circle, but he didn’t reduce truth to sincerity.
🧠 Modern Minds Speak Up: Contemporary Theologians
🧔🏻 C.S. Lewis (1898–1963)
Lewis, the beloved author of Mere Christianity, was sharp on this point. He warned that believing a falsehood with passion doesn’t transform it into truth.
“A man may be sincerely wrong… sincerity does not make error into truth.”
— The Problem of Pain
To Lewis, sincerity may soften your manners, but only truth brings salvation.
🧍♂️ Billy Graham (1918–2018)
Billy Graham preached to millions and emphasized the grace and love of God. Yet, he was unwavering on the need for faith in Christ alone.
“You may be sincere in what you believe, but if you are wrong, you are wrong eternally.”
— Crusade Sermon, 1978
He didn’t minimize the emotions or motivations of others—but sincerity without Christ? That wasn’t enough.
📖 R.C. Sproul (1939–2017)
A defender of Reformed theology, Sproul was a critic of relativism and moral vagueness.
“Truth is not determined by how sincerely we believe it.”
— Essential Truths of the Christian Faith
Sproul taught that belief must be anchored in God’s revealed truth, not just emotional conviction.
🕊️ Tim Keller (1950–2023)
Keller often addressed secular and skeptical audiences. He acknowledged the emotional comfort of sincerity, but always pointed back to the gospel’s objective truth.
“If truth is relative, then sincerity becomes the highest virtue—but that’s a poor substitute for truth itself.”
— The Reason for God
✝️ N.T. Wright (b. 1948)
Wright is a contemporary New Testament scholar who speaks with both compassion and clarity. He admits that many people around the world sincerely seek God—but he’s clear that Jesus is the center.
“Christianity makes radical claims—not about our sincerity, but about the identity of Jesus.”
— Simply Christian
📖 What Does the Bible Say?
The Bible doesn’t shy away from this issue. In fact, it speaks directly to it:
“There is a way that seems right to a man, but its end is the way to death.”
— Proverbs 14:12
“I am the way, and the truth, and the life. No one comes to the Father except through me.”
— John 14:6
“And there is salvation in no one else, for there is no other name under heaven given among men by which we must be saved.”
— Acts 4:12
Sincerity does not override the need for truth.
🎨 Illustration: The Poisoned Cup
Imagine someone hands you a cup of clear water. You drink it down sincerely, believing it to be pure. But it was laced with a slow-acting poison.
Your sincerity doesn’t change the result.
Likewise, wrong beliefs—even held with heartfelt sincerity—can still lead to spiritual ruin.
🧭 The Road to Salvation: Truth First, Then Heart
The Christian faith has always taught that the content of faith matters. What we believe—specifically about Jesus—is the dividing line.
Jesus didn’t say, “Just believe something as long as you’re earnest.” He said:
“Repent and believe the gospel.” — Mark 1:15
The truth is not something we create, but something God has revealed. Faith is not about making our own path, but trusting the One who is the Way.
🧵 Why This Matters: The Heart of the Gospel
If sincerity alone could save, then Jesus did not need to die.
Why the Cross? Why the sacrifice? Because truth has a cost. If salvation could be gained through any heartfelt belief, then Calvary was unnecessary.
But the gospel says differently:
“Christ died for our sins in accordance with the Scriptures.”
— 1 Corinthians 15:3
We need more than good intentions. We need a Savior.
🧠 Final Thoughts from Our Church Bench
Here in our little churches under the shadow of Mount Hood, we’ve seen the heartbreak of broken paths—folks who meant well, but followed lies. We’ve also seen the life-changing power of Jesus Christ.
Our job is not to condemn the sincere seeker—but to gently point them to the truth that sets them free.
“Then you will know the truth, and the truth will set you free.”
— John 8:32
So next time someone says, “It doesn’t matter what you believe as long as you’re sincere,” you might kindly ask:
“But what if you’re sincerely wrong?”
Then share the truth in love—because truth with love is the way of Christ.
📚 References
- C.S. Lewis, Mere Christianity, HarperOne, 2001.
- Augustine, Confessions, translated by R.S. Pine-Coffin, Penguin Classics.
- John Wesley, A Plain Account of Christian Perfection, 1766.
- R.C. Sproul, Essential Truths of the Christian Faith, Tyndale House.
- Billy Graham, Peace with God, Thomas Nelson.
- Tim Keller, The Reason for God, Dutton, 2008.
- N.T. Wright, Simply Christian, HarperOne, 2006.
- Justin Martyr, First Apology.
- The Holy Bible, ESV, Crossway.
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