Some Christians have such a distorted view of their own worth, they feel the need to jump down anyones throat if they dare disagree.
That is their biggest fault in my eyes. They would earn more respect by dutifully living their life as they see fit, without criticising/insulting people of opposing views.
I do not jump out at folks in the street and try and wave a copy of the Sears catalogue under their noses, so why do they do it with the bible.