The sin is referring to the work of the holy spirit, as in healing and such, as work of the Devil instead of the holy spirit. I'm not sure how it can be more specific. Maybe try reading well before, then up to the verse I posted. If I recall there are several verses in between the time it happens and the verse with Jesus warning. And maybe try a few translations....that could help
And you mention your knowledge of blasphemy and that's fine but I'm just saying general blasphemy is one thing and blasphemy against the holy spirit is another thing altogether. Also, if I'm not mistaken somewhere is says the Father will even put up with Blasphemy against Christ, and forgive that, but for some reason, doing so against the Holy Spirit, strikes a sore spot with God that we don't want to mess with.
I've heard all the "The only unforgivable sin is not accepting Christ" as well as other twists, but that/they simply aren't true. That's what some preachers do, teach a "Higher Knowledge" than what is biblical, makes themselves look good to some who don't bother checking them out, of don't know any better, and the next thing we know, people think it's a fact. Things like that happen often with scripture and it's so dangerous, God has some grave warnings about doing it.
Hope that helps some anyway.
