Question about the unforgivable sin?

I think that is a misunderstanding. That idea came more from tradition than from the Bible. The Bible doesn't say it is blasphemy, God says if you deny him, he'll deny you. I.e., if you don't come to him (become a Christian), he'll not accept you. Most people who "blaspheme" don't really know who they are speaking against. If you truly knew who God was, but still were against him, I don't think you'd ever "see the light" or even want to be a Christian anyway. That's what the demons did, and they'll never want to repent, and so will not be accepted by God. They knew exactly what they were doing. If you want to come to God, that means that you haven't committed a unforgivable sin. If you had, you'd never want to come to him. God says he'll never turn away those who come to him.