Blasphemy of the Holy Spirit

Today my mother asked me "What do you think blasphemy against the Holy Spirit...", at this point I had already begun to prepare my answer because I'm used to having this sentence end, "is".

Then my mom threw me for a loop when she said, "looks like".
Usually I would say, "It is when someone rejects God all the way to their grave, like Stalin who shoke his fist at God and die".

What does it look like though? This would suggest we could seal our eternal fate before death?.

What do you think?

And so I tell you, every sin and blasphemy will be forgiven men, but the blasphemy against the Spirit will not be forgiven.
-Matthew 12: 31 (NIV)

I'll let you determine context. Unless you're being stupid, then I'll politely tell you, "You're being stupid"!