sins against the holy spirit

“Whoever blasphemes against the Holy Spirit never has forgiveness, but is guilty of an eternal sin. There are no limits to the mercy of God, but anyone who deliberately refuses to accept his mercy by repenting, rejects the forgiveness of his sins and the salvation offered by the Holy Spirit. Such hardness of heart can lead to final impenitence.”

This sin blocks the person's route to Christ, who is the only one who can take away the sin of the world, and the sinner puts himself outside the range of God's forgiveness. In this sense, the sins against the Holy Spirit cannot be forgiven.