The Unforgivable Sin
There are many difficult questions to answer in Christianity. Does God stand outside of time? What was Paul’s thorn in the flesh? Who really was the streaker in Mark’s gospel? But one that has always challenged me is the nature of the unforgivable sin.
The Sin in Scripture
In Luke 12:10, Jesus tells us that what a man blasphemes “to the Holy Spirit” (εἰς τὸ ἅγιον πνεῦμα) will not be forgiven. In two other passages, we hear Christ make this declaration in a specific context:
“But when the Pharisees heard it, they said, ‘It is only by Beelzebul, the prince of demons, that this man casts out demons.’
“Knowing their thoughts, [Jesus] said to them… ‘I tell you, every sin and blasphemy will be forgiven people, but the blasphemy against the Spirit will not be forgiven. And whoever speaks a word against the Son of Man will be forgiven, but whoever speaks against the Holy Spirit will not be forgiven, either in this age or in the age to come’” (vv. 24–25, 31–32).
“‘Truly, I say to you, all sins will be forgiven the children of man, and whatever blasphemies they utter, but whoever blasphemes against the Holy Spirit never has forgiveness, but is guilty of an eternal sin’— for they were saying, ‘He has an unclean spirit’” (vv. 28–30).
We can rightly understand these passages by placing them alongside a few more. In 1 John 5:16–17, John writes,
“If anyone sees his brother committing a sin not leading to death, he shall ask, and God will give him life—to those who commit sins that do not lead to death. There is sin that leads to death; I do not say that one should pray for that.”
Intentionally not praying may seem like a strange concept, but we find parallels to it in Jeremiah 7:16 and 11:14, where God commands Jeremiah not to pray for the people. More directly, the author of Hebrews says,
“…it is impossible, in the case of those who have once been enlightened, who have tasted the heavenly gift, and have shared in the Holy Spirit, and have tasted the goodness of the word of God and the powers of the age to come, and then have fallen away, to restore them again to repentance, since they are crucifying once again the Son of God to their own harm and holding him up to contempt” (Hebrews 6:4-6).
Some Not-So-Helpful Theories
Now, there have been a lot of bad theories concerning the identity of the unforgivable sin. Those who claim it is murder or adultery would exclude David and others. Fornication and suicide would exclude Samson who made the Hebrews “Hall of Faith.” If we say it is any kind of blasphemy, that would exclude Paul, who wrote in 1 Tim 1:13, “though formerly I was a blasphemer, persecutor, and insolent opponent. But I received mercy because I had acted ignorantly in unbelief.”The Didache saw the Matthew passage specifically as the testing of a prophet while making prophesy.
Joel Green claims that “for Luke, blasphemy of the Holy Spirit refers to committing apostasy in the face of persecution.” Granted, we sometimes see cases of apostasy that are (at least from our perspective) hopeless. John Foxe records the story of Nichomachus in the 3rd century who initially refused to sacrifice to pagan idols. After torture, he recanted and denied Christ. But immediately after recanting, he fell down in agony and died. At the sight of this, a 16-year-old Christian woman, Denisa, exclaimed, “O unhappy wretch, why would you buy a moment’s ease at the expense of a miserable eternity!” She then faced her death without faltering.
Yet even those who deny Jesus and His message may be forgiven if they repent. There is hope for Pharisees, just as there was hope for the Apostle Peter, Thomas Cranmer, and any who ultimately returns to claiming Christ.
Trapped in an Iron Cage
Because Christ calls the unforgivable sin “blasphemy against the Holy Spirit,” it’s helpful to understand what is meant by “blasphemy.” The term is defined as speaking “in a disrespectful way that demeans, denigrates, maligns” and comes from two words joined together that mean “to harm” and “a report, news.” The idea of blasphemy, especially in this context, is to denigrate the Holy Spirit (and the entire Godhead) in such a way that it harms the message of the truth. But, as we noticed in the phrasing of Luke 12:10, the term may also indicate that the blasphemy is directed towards (εἰς) the Holy Spirit.
So what is this sin? It is a pattern that has led a person into such a rejection of Christ and the Gospel that they cannot come to a point of repentance. Such a state is depicted in Bunyan’s metaphor of the man in the iron cage in Pilgrim’s Progress. There the man tells Christian,
“I left off to watch and be sober; I laid the reins upon the neck of my lusts; I sinned against the Light of the Word, and the Goodness of God; I have grieved the Spirit and he is gone; I tempted the Devil, and he is come to me; I have provoked God to Anger, and he has left me; I have so hardened my heart that I cannot repent… God hath denied me repentance. His word gives me no encouragement to believe…”
There is a narrow view that is certain and clear in the context of the Matthew and Mark passages. It is where the Holy Spirit has made a man conscious of the truth of Christ and the Gospel, but they knowingly rejected the Son of God, especially to deter others from following Him. This would also tie into what we call “the sin of the high hand” under Mosaic Law, which was unforgivable in its own way (Numbers 15:30). It’s called the blasphemy of the Holy Spirit instead of Jesus because those who recognized the presence and work of God the Holy Spirit in Christ. They claimed that Jesus’ power was from the Devil. It is a peak form of what is lamented in Isa 5:20, “Woe to those who call evil good and good evil, who put darkness for light and light for darkness, who put bitter for sweet and sweet for bitter!”
On the incident in Matt. 12, John Martin writes,
“Apparently the Pharisees were being convicted by the Holy Spirit that Jesus was indeed the Messiah, but were rejecting His witness. They could never be forgiven because they were rejecting God’s only means of salvation. (In contrast to that, a number of Jesus’ own brothers who initially rejected Him [John 7:5] later came to faith [Acts 1:14] and were forgiven even though they had spoken against the Son of Man.)”
To this R.C. Sproul adds, “[What] Jesus is defining here is a specific type of blasphemy: a calling of Jesus the devil, as the worst and most gross form of blasphemy we can think of.” And according to Norval Geldenhuys, this sin is “a conscious, willful, intentional blasphemy of the clearly recognized revelation of God’s grace in Christ through the Holy Ghost, a revelation which nevertheless out of hate and hostility is ascribed to the devil.”
Godet gives an interesting perspective on Christ’s original audience:
“The history of Israel has fully proved the truth of this threatening. This people perished not for having nailed Jesus Christ to the cross. Otherwise, Good Friday would have been the day of their judgment, and God would not have continued to offer them for forty years the pardon of their crime. It was the rejection of the apostolic preaching, its obstinate resistance to the Spirit of Pentecost, which filled up the measure of Jerusalem’s sin. And it is with individuals as with that nation. The sin which is forever unpardonable, is not the rejection of the truth, in consequence of a misunderstanding, such as that of so many unbelievers who confound the gospel with this or that false form, which is nothing better than its caricature. It is hatred of holiness as such, a hatred which leads men to make the gospel a work of pride or fraud, and to ascribe it to the spirit of evil. This is not to sin against Jesus personally; it is to insult the divine principle which actuated him.” 
But this draws us into a broader understanding of the sin. It isn’t only when men say that Jesus derived His power from Satan. It is where sin has taken possession of the soul and its grip is never released. As John Owen said, the only thing that ever actually bars someone from heaven is unrepentant unbelief. It is rarely truly known until a person enters the grave still rejecting Christ’s Gospel. Heb 2:3-4, “…how shall we escape if we neglect such a great salvation? It was declared at first by the Lord, and it was attested to us by those who heard, while God also bore witness by signs and wonders and various miracles and by gifts of the Holy Spirit distributed according to his will.” What seems to best suit all passages is the persistent resistance and willful hardening of the heart to the testimony of the Holy Spirit concerning the Gospel of Christ, which would coincide with Matt 7:6 in terms of both testimony and prayer.
Leon Morris writes,
“We must understand this, not of the uttering of any form of words, but of the set of the life (‘It denotes the conscious and wicked rejection of the saving power and grace of God towards man). This blasphemy is so serious because it concerns the whole person, not a few words spoken on any one occasion… People in such a situation cannot repent and seek forgiveness: they lack a sense of sin; they reject God’s competence to declare what is right.” And also JC Ryle, “…to be called a Christian, and know the theory of the Gospel, and yet cleave to sin and the world with the heart, is to be a candidate for the worst and lowest place in hell.—It is to be as like as possible to the devil.”
And Calvin closes this section for us.
“Those who are destitute of the light of the Spirit, however much they may detract from the glory of the Spirit, will not be held guilty of this crime… no man curses the Spirit who is not enlightened by him, and conscious of ungodly rebellion against him; for it is not a superfluous distinction, that all other blasphemies shall be forgiven, except that one blasphemy which is directed against the Spirit… As we maintain, that he who has been truly regenerated by the Spirit cannot possibly fall into so horrid a crime, so, on the other hand, we must believe that those who have fallen into it never rise again; nay, that in this manner God punishes contempt of his grace, by hardening the hearts of the reprobate, so that they never have any desire towards repentance.”
Why This Matters
When we bring these things into balance, it calls us to serious self-examination and caution. It calls us to make our calling and election sure, to work out our salvation with fear and trembling. We might tell ourselves that we would never deny Christ, but we have all turned away from Him in a thousand little ways. Every time we disobeyed His law, it was an act of unbelief. Every heart-idol we have made from the good gifts of God is a denial of Christ. We might claim we are ready to die for His sake, and yet we then fail to honor (or even attend) the Sabbath worship. How many Sundays have you missed because you cared more about the opinions of people and your own comfort than the worship of the God who has loved you?
These concepts tie directly into a statement from the Westminster Confession of Faith about how faith lays hold of Scripture, “yielding obedience to the commands, trembling at the threatenings, and embracing the promises of God for this life and that which is to come.” We yield obedience to the command to confess Christ, tremble at the threatenings of an unforgivable sin, and embrace the promise that Christ will confess us and claim us before God.
If you fear that you have committed the unforgivable sin, flee to God, to Christ, in repentance and faith — and in so doing, prove that you have not committed the unforgivable sin.
Chris Marley is the pastor of Miller Valley Baptist Church in Prescott, AZ. Chris has an M.Div. from Westminster Seminary California (from the Institute of Reformed Baptist Studies). He is the author of Scarlet and White.
"Have I Committed the Unpardonable Sin?" by Richard Phillips
"Blasphemy and the Church" by Justin Poythress
"What Is Indwelling Sin?" by Daniel Miller
From Heaven He Came and Sought Her by David & Jonathan Gibson
 Joel B. Green, The Gospel of Luke: NICNT, Grand Rapids: Eerdmans. P.484
 John Foxe, Foxe’s Book of Martyrs
 Thomas Cranmer was a contemporary of Ridley and Latimer during the reign of bloody Mary in England. At first, Cranmer faltered and recanted his faith in the true Gospel to avoid execution. But his courage returned. He repented of his sin, retracted his recanting, and went courageously to his death preaching Christ.
 A Greek-English Lexicon of the New Testament and Other Early Christian Literature: 3rd ed (BDAG)
 John Bunyan, The Pilgrim’s Progress, Uhrichsville, Barbour. P.39
 John Martin, Bible Knowledge Background Commentary digital edition
 RC Sproul, A Walk With God: Luke digital edition
 Cited by Philip Graham Ryken, Reformed Expository Commentary: Luke digital edition
 Frederick Louis Godet, Commentary on the Gospel of Luke Grand Rapids: Zondervan. P.93
 John Owen, Hebrews
 Leon Morris, Tyndale Commentary: Luke digital edition
 J.C. Ryle, J.C. Ryle Collection: Luke digital edition
 John Calvin, Calvin’s Commentaries: Luke digital edition
 WCF XIV:II