Truly I say to you, all sins shall be forgiven the sons of men, and whatever blasphemies they utter: but whoever blasphemes against the Holy Spirit never has forgiveness, but is guilty of an eternal sin. (Mark 3:28-29)
And everyone who will speak a word against the Son of Man, it shall be forgiven him; but he who blasphemes against the Holy Spirit, it shall not be forgiven him. (Luke 12:10)
It seems that for every form of blasphemy forgiveness is available if there is repentance. But supposing you repent of blasphemy against the Holy Spirit? Is there no forgiveness?
As always when we read the Bible, we should look at the context, the setting, of the passage we want to understand. We can prove just about anything if we lift quotations from their place in the thought of the writer. If we look at the passage from Mark, we shall see that Jesus charged some scribes with blaspheming against the Holy Spirit because they saw people healed of various sicknesses and of insanity, and did not doubt the reality of these cures, but instead of giving God the glory, they accused our Lord of being an agent of Satan: He has an unclean spirit. These miracles were a sign that God was active in the ministry of Jesus: If it is by the finger of God that I cast out demons, then the kingdom of God has come upon you. If they believed that he was bringing wholeness to the minds and bodies of men and women thorugh the power of Satan, then they had closed their eyes to the light. They refused to see that actions which were good were in fact good in themselves, and they refused because they disapproved of the person, Jesus, who was responsible for them. Light had become darkness and good had become evil. They committed a sins, but do not know they are sinning. If they refuse the light, where else can they hope to receive illumination, for, in the words of the psalmist, it is in thy light, Lord, that we see light.
Luke gives a different emphasis. He places this saying between two other sayings. One is:
I tell you, every one who acknowledges me before men, the Son of man will also acknowledge before the angels of God; but he who denies me before the men will be denied before the angels of God. (Luke12:8-9)
The other is:
And when they bring you before the synagogues and the rulers and the authorities, do not be anxious how or what you are to answer or what you are to say; for the Holy Spirit will teach you that very hour what you ought to say. (Luke 12:11-12)
Mark (13:11) and Matthew (10:20) both have parallels to this saying.
Its setting in Luke gives it a different emphasis from Mark. There is the suggestion that blaspheming the Holy Spirit involves refusing his help when it is available to save Jesus' disciples from denying him. If this is so, then blaspheming against the Holy Spirit is really apostasy, that is, denying Jesus as Lord. We can see in Hebrews 6:4-6 how grievous the sin of apostasy is.
For Mark, then the sin against the Hoy Spirit involves deliberately shutting one's eyes to the light and calling good evil. In Luke it is final apostasy, turning away from God's salvation. The sin against the Holy Spirit is not so much an isolated act but a state of mind. The more we judge through prejudice, the more we we distort our own motives and the motives of other people, the more steadily we enter darkness and the more relentless is the movement towards not being able to tell good from evil.