Nope, he clearly stated that human nature has something to do with this intolerant attitude. Therefore I believe he was not only referring to christians but to the dominant culture during his time.
There was a time when majority of the people believed that the earth was flat. They were very sincere with this belief, and it was also considered "common sense" during that time. So It's not sincerity or faith towards a particular belief that humans need.
It is humility and skepticism. "Doubt is humble."
That is why learning to say "i don't know." is the first step towards growth and knowledge. hehe.




guess everyone here wants to know too..

