Others have shared about the broad meaning: resist the convicting power of the holy spirit all the life will guarantee a place in hell.

I now turn to the contextual and perhaps narrower meaning for blasphemy to the holy spirit. Let's examine the passage at hand (Matthew 12).

When Jesus was walking on earth, he healed many sick persons and those who were possessed by evil spirit. But the unbelieving Jews (especially pharisees) slandered Jesus to be a witchcraft that cast out demons by the power of Satan (Beelzebub the prince of the demons). Jesus reasoned with them that their logic did not hold water. He went on to warn them that anyone who spoke against the holy spirit will not be forgiven, neither in this world, nor in that which is to come.

Thus the narrower meaning for blasphemy of the holy spirit is this: to slander the mighty work of the holy spirit as the apparent work of the devil. In a nutshell, it is to equate holy spirit with the evil spirit.

That is really a stern warning. Basically all sinners who intentionally blaspheme the Holy Spirit will never have a chance to be forgiven, not even in this life! Oh what poor soul!

Take Bach for example, he is a very canny man in the sense that even though he boldly cursed Jehovah God a few times, but he never dares to curse the holy spirit. He often compliments Jesus by saying that he loves the sermon on the mount. I surely hope God the Father will have mercy on him. I am a little skeptical since God the Father often calls the shots in human affairs. He sent his one and only son Jesus and then, jointly with Jesus, sent the holy spirit. (Again so much for the unipersonal monotheism.) God the father is calling key shots, albeit in full counsel with the Son and the holy spirit all the while.

Take some other preschooler kid who slanders our God and faith, but he never dares to curse the holy spirit. You see, even sinners like that have reservation to speak against the holy spirit. I have to admire their prudent cowardice in this case. Peace.

Matthew 12:22 当下有人将一个被鬼附着、又瞎又哑的人、带到耶稣那里．耶稣就医治他、甚至那哑巴又能说话、又能看见。

12:23 众人都惊奇、说、这不是大卫的子孙么。

12:24 但法利赛人听见、就说、这个人赶鬼、无非是靠着鬼王别西卜阿。

12:25 耶稣知道他们的意念、就对他们说、凡一国自相分争、就成为荒场、一城一家自相分争、必站立不住。

12:26 若撒但赶逐撒但、就是自相分争、他的国怎能站得住呢。

12:27 我若靠着别西卜赶鬼、你们的子弟赶鬼、又靠着谁呢．这样、他们就要断定你们的是非。

12:28 我若靠着　神的灵赶鬼、这就是　神的国临到你们了。

12:29 人怎能进壮士家里、抢夺他的家具呢、除非先捆住那壮士、才可以抢夺他的家财。

12:30 不与我相合的、就是敌我的、不同我收聚的、就是分散的。

12:31 所以我告诉你们、人一切的罪、和亵渎的话、都可得赦免．惟独亵渎圣灵、总不得赦免。

12:32 凡说话干犯人子的、还可得赦免．惟独说话干犯圣灵的、今世来世总不得赦免。