Mark 3:28-30 finds a parallel reference in Matthew 12:31-32 which says, “And whosoever speaketh a word against the Son of man, it shall be forgiven him; but whosoever speaketh against the Holy Spirit, it shall not be forgiven him, neither in this world, neither in the world to come.” Speaking against the Holy Spirit is denying the power of God.
In the context of these passages, the Pharisees were making false accusations against our Lord and denying the power Jesus used to miraculously heal the afflicted as coming from God. Although they were familiar with the Old Testaments scriptures (quoted in verses 18-21) which spoke of the works of the Messiah that would come, they renounced Jesus’ relationship to God and called him the child of Beelezub, that is, the devil. It was to this accusation that the Lord responded saying that anyone who denies the power of God, shall not be forgiven, neither in this world or the world to come.
There is a principle that is involved in this announcement. The Holy Spirit is the spirit of truth (John 15:26) and so anyone that is educated in the truth is responsible for that knowledge. They would be going against their conscience in denying that truth. This was the case with the Pharisees. They refused to accept, through hardness of their hearts, what they had witnessed. It was a sin against light, a sin of what they knew to be right.
This principle also applies to the Christian of this Christian era. Hebrew 6:4-8 read, “It is impossible for those who were once enlightened, and have tasted of the heavenly Gift and were made partakers of the Holy Spirit, and have tasted the good Word of God and the powers of the world to come, if they shall fall away, to renew them again unto repentance; seeing they crucify it to themselves the Son of God afresh and put him to an open shame.” What is this sin? It is not one sin but rather living a life contrary to the will of God and the denying the value of the blood by which we have been saved. A life contrary to God’s will would be living as hypocrites with hardness of heart. Essentially, in public a person might behave righteously, but in private his heart would be far from Christ-like. We need to ask ourselves: Do we love the Lord above all else? Are we willing to suffer as did our Lord? Do we recognize that without Jesus we have no standing with God? Are we striving to avoid all sin and enable the power of God to work in our hearts? If that is so, then we are being transformed into Christ-likeness and not blaspheming against the Holy Spirit.