The Unpardonable Sin

Mark 3:22-30 ESV

And the scribes who came down from Jerusalem were saying, "He is possessed by Beelzebul," and "by the prince of demons he casts out the demons." And he called them to him and said to them in parables, "How can Satan cast out Satan? If a kingdom is divided against itself, that kingdom cannot stand. And if a house is divided against itself, that house will not be able to stand. And if Satan has risen up against himself and is divided, he cannot stand, but is coming to an end. But no one can enter a strong man's house and plunder his goods, unless he first binds the strong man. Then indeed he may plunder his house. "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."

 Hebrews 10:26-31 ESV

For if we go on sinning deliberately after receiving the knowledge of the truth, there no longer remains a sacrifice for sins, but a fearful expectation of judgment, and a fury of fire that will consume the adversaries. Anyone who has set aside the law of Moses dies without mercy on the evidence of two or three witnesses. How much worse punishment, do you think, will be deserved by the one who has spurned the Son of God, and has profaned the blood of the covenant by which he was sanctified, and has outraged the Spirit of grace? For we know him who said, "Vengeance is mine; I will repay." And again, "The Lord will judge his people." It is a fearful thing to fall into the hands of the living God.

 These are two of the most difficult passages in the Scriptures. If you didn't actually read it before you started reading this, scroll back up and do so. 
The reason I want to look at these and draw for you the connection that I believe is there is because over a year ago I had a student in youth group ask the question that most people ask after reading Mark 3- "If blasphemy against the Spirit is the only unpardonable sin, what then, is blasphemy against the Spirit?" It's a very reasonable question. If Jesus says this is the only thing you can do that you won't be forgiven of, we probably want to know what it is and avoid it, right? 
And yet the footnotes in most Bibles, and the off-the-cuff conjectures of youth leaders, seem to most generally ring hollow when it comes to answering that question. And the question bugged me, so I researched, listening to sermons and checking commentaries, and all it seemed to lead to was more confusion for me. And so I came to the conclusion that it was just one of those things I'd never quite understand. Which sounds all well and fine, unless you know me, and then you would realize how bonkers such a conclusion would drive me. But there wasn't a lot I could do about it. 

So there's the preface, essentially, that an intelligent and inquisitive student asked a good question that I found no solid answer for. I want to preface with that because those pastors, and theologians, and whoever it is that writes study Bibles are obviously a lot smarter than me. So if they can't find something solid, then maybe I'm foolish to think that I understand it. Take what you're about to read with a grain of salt. Prayerfully consider if what is discussed is present in your life. If so, repent. Anyone willing to repent is not beyond forgiveness, 

1 John 1:9 ESV
If we confess our sins, he is faithful and just to forgive us our sins and to cleanse us from all unrighteousness. 

 So let's do just a little bit of context work with each of these passages, and then draw the connection. 

First we have the passage in Mark three. What is happening? Jesus has been royally annoying the scribes and Pharisees. How? By doing things like healing a man with a withered hand on (gasp!) the Sabbath, forgiving sins, and the issue at hand here, casting out demons. This has not made him at all popular with the local religious leaders. So what do they do? They accuse Him of casting out demons by the power of Satan, rather than the power of God. And Jesus responds with parables, that is, stories with a point. Stories about a house divided being unable to stand, and about it being impossible to plunder a strong man's house without first binding said strong man. The point Jesus makes is clear-Satan can't be casting out demons, because he'd be working against himself, and for anyone else to cast them out, Satan must be bound. Jesus makes it exceedingly clear that what they are accusing Him of is not only false, but absolutely ludacris. It is after all this that He makes the statement that all blasphemies will be forgiven except blasphemy against the Spirit, for that is an eternal sin. 

 Let's now shift our gaze on over to Hebrews 10. A quick side note here, I've read through Hebrews several times recently, and it is exceedingly rich and helpful. If you haven't read it lately, take the 30-55 minutes (depending on how quickly you read) and just read it straight through. It will be time well spent. That being said, obviously the context of Hebrews is a little different than that of Mark. We have an unknown writer writing to an unknown, although presumably Jewish, audience. A large part of the book deals with how Jesus is supremely better and above everything and everyone else. Jesus is above angels, Jesus is better than Moses, Jesus is the Great High Priest, Jesus' priesthood is better than the Levitical priesthood, the Covenant Jesus establishes is better than the old Covenant, and the beginning of chapter ten deals with Jesus sacrifice being better than the continual sacrifices of the blood of bulls and goats, for His not only atones for, but removes sin. That's the backdrop of what we read in verses 26-31. Jesus fulfills and supersedes the old things. Jesus has, through His blood, allowed us to have our sins forgiven by God, and God makes us His people. 
Now here in verses 26-31 we see, essentially, what happens when you reject that. 

First we need to see here that knowing the truth is not enough. Obedience is what God requires (for a longer treatment of that, you can go back to my sermon on Matthew 7).
The writer tells us that if we have a knowledge of the truth, and yet continue to sin deliberately, we no longer can expect forgiveness, but rather the wrath of Almighty God. Anyone who broke Moses law was put to death based on two or three witnesses-how much worse to have God against you for spurning His Son, trampling the blood, and thus outraging the Spirit! It is a fearful thing to fall into the hands of the living God. 

So, what is the connection? I think what we see here are really very similar things, similar sins, that share a common end. In Mark we have the Pharisees, people who know the Jewish Scriptures better than anyone else. They are seemingly very dedicated to God. And yet when the Messiah comes, preaching good news, healing the sick, casting out demons, and forgiving sins, they who should be the first to recognize, embrace, and worship Him instead are suspicious, malicious, amd accusatory. They have no excuse for not seeing, Jesus makes it clear to them who He is, and yet they reject Him. They take the clear work of God the Holy Spirit and attribute it to Satan.
In Hebrews we see a person described who has a knowledge of the truth. Perhaps they are even like the people in Matthew seven who think they are doing good works and following God. But there are areas of clear sin in their lives that they refuse to confess and repent. They know the truth and yet continue to deliberately sin. They can see the Son of God and what He did, and refuse to accept His sacrifice. Their sin is sweeter to them than the grace of Jesus. 
The power of the Pharisees was sweeter to them than worshipping the God they claimed to serve. 

 To conclude. I think we sometimes seperate out verses like Mark 3:28-29, and try to figure out their meaning apart from their obvious context. If I just throw out the phrase "blasphemy againt the Spirit" without context, then of course it will be confounding and confusing. But I really believe that Jesus is clear that what is happening is not ambiguous at all. Rather, these people clearly know the truth. They are able to see God at work. And yet they reject Him. In Hebrews, there are people who know the truth, who know that Chirst will purify them, but the reject Him in favor of their sin.  

The question is, why is this unforgivable? It does not state this black and white in the text, so take it for what it is, merely my opinion.
What is the only condition of forgiveness? Repentance and faith. Confess your sins, and believe that God forgivess you because of Christ. So it would seem to me that the reason the sin of blaspheming the Holy Spirit is unforgivable because it impedes our ability to repent. It kills the seed of faith. To look at the work of God, and know it is the work of God, and yet reject Him- this cannot coexist with faith. And a faithless heart is an unforgiven heart.