Blasphemy

Blasphemy: The Unforgivable Sin—and What It Isn’t

There are few phrases in Scripture that strike fear more deeply into the hearts of believers than “blasphemy against the Holy Spirit.” Many Christians have spent sleepless nights wondering if they’ve committed it—usually without even knowing what it actually is. Like many spiritual terms, blasphemy has suffered from misuse, misdefinition, and misunderstanding. This article seeks to restore biblical clarity to the concept, showing what it meant then, what it means now, and why it matters.

What Is Blasphemy?

The Greek word used throughout the New Testament is βλασφημία (blasphēmia), Strong’s G988, which refers to “slander, abusive speech, or irreverent speech against God.” It’s from the root βλάσφημος (blasphēmos), meaning someone who reviles or insults deity.

In simple terms, blasphemy is deliberate dishonor or slander against God’s character, nature, or work—usually expressed in speech but not limited to it.

The Hebrew equivalent is נָקַב (naqab, Strong’s H5344), which in Leviticus 24:16 implies to pronounce distinctly or explicitly, used in the context of invoking or cursing the divine name.

“Anyone who blasphemes the Name of the Lord must be stoned to death by the whole community of Israel. Any native-born Israelite or foreigner who blasphemes the Name of the Lord must be put to death.” (Leviticus 24:16, NLT)

This was not casual swearing—it was a public, knowing, and hostile dishonoring of God’s revealed identity. In Old Testament law, blasphemy against God was capital-level rebellion.

New Testament Examples: God, Christ, and the Spirit

In the New Testament, blasphemy broadens to include false or slanderous accusations against God the Father, the Son, or the Spirit, as well as twisting or maligning His works.

Jesus Accused of Blasphemy

Ironically, the most frequent target of blasphemy accusations in the Gospels was Jesus Himself:

“Why does this man speak that way? He is blaspheming! Who can forgive sins but God alone?” (Mark 2:7, LEB)

Jesus was accused of blasphemy for claiming divine authority—because if His claims weren’t true, they would be blasphemy. But of course, they were true, and the actual blasphemers were His accusers.

Blasphemy Against the Holy Spirit

Now we come to the phrase that keeps believers up at night. Jesus said:

“I tell you the truth, all sin and blasphemy can be forgiven, but anyone who blasphemes the Holy Spirit will never be forgiven. This is a sin with eternal consequences.” (Mark 3:28–29, NLT)

Context is everything. In this scene, the religious leaders accuse Jesus of casting out demons by the power of Satan (Mark 3:22). Jesus calls this not just wrong but spiritually suicidal. Why?

They weren’t ignorant. They saw the Spirit of God at work—and willfully called it demonic. This is not a passing doubt, or a fearful question. This is deliberate rebellion by those who knew better.

To blaspheme the Holy Spirit is to harden your heart in a state of willful rejection, seeing the work of God and calling it evil. It is, in effect, to say “no” to salvation forever.

It’s not a sin you stumble into. It’s a condition you persist in.

1 John 5:16–17 – The Sin That Leads to Death

“If you see a fellow believer sinning in a way that does not lead to death, you should pray, and God will give that person life… But there is a sin that leads to death, and I am not saying you should pray for those who commit it.” (1 John 5:16–17, NLT)

Many believe this passage refers indirectly to the same heart posture Jesus spoke of—a settled, hardened rejection of the truth. Some link it to blasphemy against the Spirit, others to apostasy (Hebrews 6, 10), or even to a judicial act of God ending someone’s life.

Regardless, it reinforces the same truth: not all sin is the same. Some sin is stubborn to the point of spiritual ruin.

Hebrews 10:26–29 – “There No Longer Remains a Sacrifice”

“Dear friends, if we deliberately continue sinning after we have received knowledge of the truth, there is no longer any sacrifice that will cover these sins.” (Hebrews 10:26, NLT)

This is not about someone who slips or struggles. It is about someone who knows the truth, professes it, and then despises it—even mocking the work of Christ and the Spirit.

“…just think how much worse the punishment will be for those who have trampled on the Son of God… and who have insulted and disdained the Holy Spirit who brings God’s mercy to us.” (Hebrews 10:29, NLT)

This “insult” to the Spirit is often viewed as parallel to blasphemy against Him.

Revelation and Blasphemy

In the Book of Revelation, blasphemy is one of the defining traits of the beast and his system:

“And the beast was allowed to speak great blasphemies against God…” (Revelation 13:5, NLT)

This symbolizes open, systemic defiance against God—something very different from the personal fears of believers who worry they’ve somehow slipped up.

Modern Misunderstandings

Many people think they've blasphemed because they:

• Said something flippant about God

• Had a wicked thought

• Mocked Christianity in the past

• Took God's name in vain before they were saved

None of those are the blasphemy Jesus is talking about in Mark 3. Are those sins? Yes. Are they unforgivable? No.

The only unforgivable sin is the one that rejects forgiveness itself.

So Why Is It “Unforgivable”?

Because it rejects the very means of forgiveness. The Holy Spirit is the One who convicts, illuminates, and regenerates. If you resist Him permanently—calling His work evil, and your sin good—you’re closing the door God opened.

And if you’re worried you’ve committed it, you haven’t. That concern proves the Spirit is still working.

Application: Guarding Against Blasphemy

1. Honor God’s name – Be careful with how you speak of Him, especially in frustration or anger.

2. Don’t slander the work of God – Avoid mocking, dismissing, or attributing godly things to evil or manipulative sources unless you're absolutely sure.

3. Stay humble – Pride is the gateway to blasphemy. The Pharisees were too proud to admit they were wrong—even as they stood face-to-face with Jesus.

4. Listen to the Spirit’s conviction – When He convicts, respond. The danger is not that He’ll stop offering—but that you’ll stop caring.

Paul warns in Titus 2:5 that when believers fail to live in a way that reflects sound doctrine—when their lives are marked by slander, rebellion, or ungodly behavior—they "bring shame on the word of God." The Greek word used here for “shame” (βλασφημῆται – blasphēmētai, from blasphēmeō, Strong’s G987) literally means to blaspheme. This is no soft rebuke. Paul is saying that our behavior can make the gospel appear false, dishonorable, or even evil to outsiders. It’s not just false teachers or outspoken atheists who blaspheme—Christians do it when they live in hypocrisy. This sobering reality underscores why holiness, love, and sound doctrine are not optional—they are part of our witness. We don't just believe the gospel; we bear it in our bodies and behavior. When we don't, we risk dragging Christ's name through the mud.

Final Word

Blasphemy is real, and it's serious. But it’s also specific. It’s not cursing. It’s not doubting. It’s not even raging in grief or stumbling in confusion.

It is deliberate, hardened, knowing rejection of the Spirit’s work. And God warns us—because He loves us enough to say: “Don’t go down that path.”

If you still fear God, you haven’t gone too far. Turn to Him. And don’t just avoid blasphemy—run headlong into reverence.