It's baiting.
They say ‘you cannot be a Christian and accept Evolution’ or one of a thousand permutations of the same zealot argument of ‘Agree with me or you are going to go to Hell’.
Follow this logic. The Bible is the Word of God. It is true. Someone who believes in God believes what He says and that His word is true.
Jesus spoke of creation and the Flood and other events in the OT as true. Peter did as well, as did other writers of the NT.
If you're going to say that they aren't true and didn't really happen, you are going to have to either call the Bible a lie, or Jesus a liar, or the writers of the Bible liars.
The problem most creationists have with this is the how someone who calls themselves a Christian, which means they claim to have believed and trusted Christ for salvation, can say that Jesus lied about what He spoke about.
That is a just too much of a stretch for someone who claims to believe God. If you believe that He is who He said He is, then you must take Him as His word.
If you pick and choose what parts you want to believe and don't trust that all of it is true, then there's no basis for believing that ANY of it is true.
If it's not reliable enough to trust in some parts, how does one reconcile the belief that it's reliable enough to believe for salvation?
It's not a matter of believing in evolution will send one to hell. It's a matter of the person claiming to be a Christian and not believing God.
So is the Pope only “claiming” to be Christian and not believing God when he says that evolution is a truth which enriches our understanding of life and being and such?
Once more your ‘argument’ is nothing more than ‘I am a Christian, and unless you believe in what I believe scripture means, you are NOT a REAL Christian, you are only claiming to be a Christian; and you are going to HELL!’.
And it need not be pointed out that is is NOT a scientific argument against evolution.