“On the basis of the bible itself. Unforgivable vs. forgivable sin.”
Thankfully, the laws of the US are earthly laws. You will have to wait for your death to find out the constitution of the heaven(The Bible) to start.
Nope, they are revealed now and we are told to live by them now.
Casuistry only steers you to hell, and that begins with hell on earth, you can’t even say you have managed to put it off till eternity.