I don't see what sincerity has to even do with what we are talking about.
The original challenge was made. Does evil have to exist for there to be free will? The OP asked for scripture to back up this point of view. So, either this is not your(I'm using 'your' in general terms) point of view, or it is your point of view, and you have failed to site scripture that defends this position.Hebrews does not even suggest that this definition is to be absolute, (I didn't say it did) so the burden is on you if you wish to take issue with my describing this as too narrow from the OP's perspective. (Since the bible says "faith is....," how does that put the burden on me? Is the bible wrong? My friend, the burden on you to demonstrate where the scripture is insufficient.) Have you never looked outside of the bible for further reading, or do all of your thoughts come from the bible alone. (Now you just sound like you are trying to pick a fight. Of course I do.) I said the definition was too narrow. (So, the bible is too narrow in it's definition of faith?) I stand by this and challenge you to show me that the Hebrews definition alone is to be kept with no further expansion. (I didn't say one could not expound on it further. I said it was adequate to describe Christian faith.) I like the Hebrews definition: I think it's great, but the OP was too narrow by sticking entirely with this definition. Frankly, it was risible! The original post had nothing to do with this.