Blaspheming the work of the Spirit
Jesus announced the good news of the kingdom of God, that the Messiah had finally come to overcome the kingdom of Satan, who had held mankind in bondage to suffering and death. The Holy Spirit demonstrated God’s victory by healing diseases, raising the dead, and casting out demons by the word of Christ. While some received the work of the Spirit with joy, others knowingly and willingly spoke against his work:
Why will these Pharisees never be forgiven? Is it because Christ did not offer them the life of the kingdom or because he did not love them enough to die for all their sins? (Calvinists tend to reason in this direction more than others.) No; rather, in rejecting the work of the Spirit through the word of their Messiah, they rejected the forgiveness that had been sincerely offered to them.
That Christ died even for their unforgivable sin is paradoxical but is clear from the doctrine of humanity’s fall through Adam’s sin: the unforgivable sin, like all actual sins, flows from the sinful nature inherited from Adam. The elect are no less sinful than those who commit the unforgivable sin. Christ atoned for the original sin of Adam (according to Romans 5) and thus for all actual sins proceeding from it.
Not every sin of unbelief or blasphemy is unforgivable. The unforgivable sin is not merely final unbelief or blasphemy against the person of the Holy Spirit, but also willing blasphemy against the work of Holy Spirit with full knowledge of doing so. For example, according to Acts, Paul washed away his sins in baptism, so he could not possibly have committed the unforgivable sin when, as an unbeliever, he forced Christians to blaspheme Christ. Also, he later said he had sinned in ignorance. By contrast, blasphemy against the Spirit is knowing and deliberate, as seen in the above case of those who accused Christ of casting out Satan by the power of Satan. May our merciful Lord keep us from that sin!
The nature of the blasphemy against the work of the Spirit is summarized by the Christian Cyclopedia’s entry on the unpardonable sin, especially the last paragraph:
Without the assurance that Christ died even for the unforgivable sin, trusting him for forgiveness becomes impossible. For if you do not believe Christ died for all the sins of the world, then how do you know whether Christ died for all of your sins? How would you know you have never committed the unforgivable sin? Without the good news that he paid for everyone’s sins, you would have to examine yourself to make sure you have never spoken against the work of the Spirit. But if the Lamb of God really takes away the sins not just of believers but of the whole world (John 1; 1 John 2; 1 Timothy 2), you have the promise that God in Christ has already reconciled you to him: