Unforgivable Sin

I realised today was Matthew 12, the unpardonable sin. I have blasphemous thoughts now but the footnote in Matthew referred to one in Mark 3 along with it, and the one in Mark seemed to suggest the unforgivable sin is refusing to recognise the HS or God as the source of Jesus's miracles. Like, so you can't be forgiven until you acknowledge God and Jesus and the HS as they are? Like it's not a one-time off to the fires it's like this can't be forgiven as long as you persist in it? Or is this wishful thinking?