In fact many pieces have been disproven/challenged only for Christians to come back and say "oh well that part's not meant to be taken literally" (re: Genesis) and "oh but that word has such a different meaning in hebrew( /greek whatever langauge they argue is translated wrong)." (re: "Truly I say to you, this generation will not pass away until all things take place"). The problem is people who believe in God are like "WELL YOU MUST PROVE HE DOESN'T EXIST!", no you the burden of proof should be on you, that's how science works; when something is hypothesised it has to be proven to be taken as knowledge. It's a bit like me saying, "there is this thing that shares all of the properties of a Christian God but it's made entirely of boobs and mars bars" and you should all worship it, you would say that is ridiculous and if I wanted you to worship it then I should prove to you that such a thing exists. Or if I said I am the richest person on earth, you'd expect me to prove that and if I said well no I am the richest person until you prove otherwise, that would seem ridiculous.