The sin that is not forgiven

This word has frightened many people. But read what comes before it. Jesus first says that all sins and blasphemies shall be forgiven. And afterwards Mark explains why he said this: because they said, He hath an unclean spirit.

It is about someone who deliberately calls God's work evil, and so keeps the door to forgiveness shut himself. That is why many pastors say: whoever is afraid of having committed this sin has certainly not committed it. A hardened heart doesn't worry about it.