To blaspheme against the Holy Spirit is to ignore the obvious evidence of the Spirit at work. Jesus, for instance, was casting out demons “by the Spirit of God,” Matthew 12:28, but the Pharisees claimed he was doing it by the power of the devil. How ridiculous, because why would the devil spite his own nose by decreasing his influence in people’s heads? Well, of course he wouldn’t do that. But if it wasn’t the devil casting out demons, there was only one other power capable of doing it – God.
But the Pharisees ignored the obvious. Like a teenager who seeks to justify contempt for his parents by accusing them of not caring when he knows full well they do care, the Pharisees also came up with outrageous accusations to bring contempt on Jesus, so long as it made Jesus look bad. And that’s what counted to them – NOT the obvious evidence of the Holy Spirit at work, but rather the chance to score points against Jesus to destroy his influence.
It’s like justifying contempt for other Christians today. Yes, other Christians have problems, they’re not perfect. Some denominations are making glaring mistakes. But they’re also doing a lot of good. They feed the poor, provide shelter, clothing, money, medication, encouragement, comfort, emergency help in disasters, education for struggling families, and they’re willing to go to the worst places on earth to help people. Their doctrines may be completely out to lunch, their churches cold and unfriendly, their manner a bit aggressive or over the top, and their emphasis on hell a bit too steep, but there’s no denying that wherever imperfect Christians are there is a lot of good being done as well.
When Jesus said in Luke 4:18, “The Spirit of the Lord is on me because he has anointed me to preach good news to the poor, proclaim freedom for the prisoners and recovery of sight for the blind, and to release the oppressed,” the evidence was overwhelming that what he said was true, because wherever he went people were relieved of demons and dreadful diseases. And all done, Jesus said, by the Holy Spirit.
We have clear evidence, therefore, of how the Spirit works. Wherever good is being done and evil is being suppressed, that’s the Holy Spirit at work. To ignore that evidence is to ignore the obvious evidence of the Holy Spirit. And to seek to score points against other Christians by focusing on their faults is to bring contempt on the Holy Spirit. That’s how easy it can be to blaspheme against the Spirit. As easy as it was for the Pharisees.