It may shock you to hear that Jesus spoke of an unforgivable sin.
You would not be alone in your shock.
In 1856, when the German poet and journalist Heinriche Heine was on his deathbed, a priest reportedly asked him if he thought God would forgive his sin. In response, Heine replied, “Of course God will forgive me; that’s his job.”
Heine’s words reflect the unspoken assumption of many people today. We imagine God to be a gentle old man passing out Werther’s Originals. When we sin, he winks at us, tells us it is ok, and hands us a piece of candy. We have a low view of God and a cheap view of grace.
By contrast, the Bible tells us that we have all sinned and fallen short of God’s perfect standard (Rom 3:23), and that what God owes us is not grace but death (Rom 6:23). Rather than being shocked that there is an unforgivable sin, we should be amazed that God would forgive any of our sin.
Mark 3:28-30
“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.”
For full context, you can read Mark 3:22-30 (see also Matthew 12:22-32 and Luke 12:8-12). Some religious leaders were saying that the reason Jesus was able to cast out demons was not because he had the power of God, but because he himself was possessed by a demon. Jesus points out the absurdity of this claim, and then goes on to warn his opponents of the seriousness of their words. They make a claim that has consequences.
This is not the only such warning in the Bible. Scripture is quite clear that sin is nothing to fool around with and that a hard heart is dangerous (for example: 1 John 4:20; Hebrews 10:26-31; Hebrews 3:7-12).
What is the Unforgivable Sin?
Bible scholar Wayne Grudem summarizes nicely (Wayne Grudem, Systematic Theology, 508).
The unforgivable sin includes: (1) a clear knowledge of who Christ is and of the power of the Holy Spirit working through him, (2) a willful rejection of the facts about Christ that his opponents knew to be true, and (3) slanderously attributing the work of the Holy Spirit in Christ to the power of Satan.
In this case it is not that the sin itself is so horrible that it could not be covered by Christ’s redemptive work, but rather that the sinner’s hardened heart puts him or her beyond the reach of God’s ordinary means of bringing forgiveness through repentance and trusting Christ for salvation.
So the person who has committed the unforgivable sin has heard the truth, rejected the truth, has hardened their heart against God, and is rejecting the work of the Holy Spirit.
This reminds me of another passage, 1 John 1:8-10.
If we say we have no sin, we deceive ourselves, and the truth is not in us. If we confess our sins, he is faithful and just to forgive us our sins and to cleanse us from all unrighteousness. If we say we have not sinned, we make him a liar, and his word is not in us.
If we confess our sin to God and ask for forgiveness, believing in Jesus as our Lord and Savior, then God gives us the gift of forgiveness. However, if we reject the conviction of sin that the Holy Spirit brings, our heart becomes hard, we do not repent, and we do not receive forgiveness.
Have I Committed the Unforgivable Sin?
You might be reading this wondering, have I committed the unforgivable sin?
Let me start by sharing some good news. If you are concerned about having committed the unforgivable sin, then you probably have not committed it.
Remember, the nature of the unforgivable sin is that it comes from a heart so hard that it is rejecting Christ and the work of the Holy Spirit. If you are feeling convicted of sin, if you desire a relationship with God, and if you would like to repent and believe in Jesus and receive salvation, then your heart is not so hard. Praise God!
However, let me also share a warning. Sin is not something to fool around with. Living in continual sin leads an increasingly hard heart.
Do not be fooled into thinking that you can just have a little and it will be enough. Do not think that you can continue just a bit longer before putting a stop to it. Be careful. Hearts aren’t hardened overnight. They become harder one step and one day at a time. Turn back before it is too late.