Blasphemy of The Holy Spirit
The one unforgivable sin, according to Jesus, is blaspheming the Holy Spirit. (Matthew 12:24-37)
What does this mean?
As with most things, context is key.
In context, Jesus has just cast out demons. His detractors, the religous leaders of the day (e.g. Phariessees, Saducees, et al) accuse Jesus of doing such signs and wonders by the power of unclean spirits, i.e. demons.
Now one may be tempted to think: "That's it? That is the one, unforgivable sin? Isn't actual, physical murder (e.g. abortion) worse? What about doing drugs? Fornicating? Adultery? What about using the NIV--or not even going to church sometimes?"
Nope, all of that pales in comparison to falsely attributing to demons what the Holy Spirit has done.
This should cuase us to wonder: have we comitted this unpardonable sin? I certainly have attributed some words and actions of other people as having come from the devil, or demons. Thankfully, in the most likely situation of that in my life (to my knowledge), it seems God backed my interpration pretty strongly, but that is a story for another day.
If that's what this is, what does that mean for the church today? Well first and most obviously, we should be careful about slinging around such accusations, especially perhaps in regards to alleged miracles, which is the situation of Jesus and the Pharisees in Matthew 12:24-37. Better just to say "Who knows?" than fire off shots of words with unmerited self confidence and without serious prayer and consideration.
Growing up, I hope I have not seen instances of this when non-charismatic Christians accuse Pentecostals (etc.) of being demonic when they speak in tongues or get "slain in the Spirit" (i.e. fall to the ground under the power of the Holy Ghost).
For these phenomena, it would seem wise to me to heed and apply the principle inherant in Paul's advice regarding the interpretation of prophecies, i.e. those alledging to be speaking under the inspiration of the Holy Spirit, as in 1 Thes. 5:20-21:
"Do not treat prophecies with contempt. But examine all things; hold fast to what is good."Likewise, 1 Cor. 14:29:
"Two or three prophets should speak, and the others should weigh carefully what is said."