The case of "blasphemy against the Holy Spirit" in the New Testament is mentioned in Mark 3: 22-30 and in Matthew 12: 22-32. The term "blasphemy" can generally be defined as a "defiant irreverence." We would apply the term to sins such as cursing God, or deliberately degrading the things concerning God. It is also to attribute some evil to God, or deny some good that we should attribute to Him. However, this case of blasphemy is a specific one, called "blasphemy against the Holy Spirit" in Matthew 12:31. In Matthew 12: 31-32, the Pharisees, despite witnessing irrefutable evidence that Jesus performed miracles in the power of the Holy Spirit, claimed that the Lord was possessed by the demon "Beelzebub" (Matthew 12:24). Now, notice that in Mark 3: 29-30, Jesus is very specific about what they exactly committed: "blasphemy against the Holy Spirit."