But there are several problems with such a defense of moderate religion. First, many moderates assume that religious "extremism" is rare and therefore not all that consequential. Happily, you are not in this camp, but I would venture that you are in a minority among religious moderates. As you and I both know, religious extremism is not rare, and it is hugely consequential. Forty-four percent of Americans believe that Jesus will return to earth to judge the living and the dead sometime in the next fifty years. This idea is extreme in almost every sense-extremely silly, extremely dangerous, extremely worthy of denigration-but it is not extreme in the sense of being rare. The problem, as I see it, is that moderates don't tend to know what it is like to be truly convinced that death is an illusion and that an eternity of happiness awaits the faithful beyond the grave. They have, as you say, "integrated doubt" into their faith. Another way of putting it is that they have less faith-and for good reason. The result, however, is that your fellow moderates tend to doubt that anybody ever really is motivated to sacrifice his life, or the lives of others, on the basis his heartfelt religious beliefs. Moderate doubt-which I agree is an improvement over fundamentalist certitude in most respects-often blinds its host to the reality and consequences of full-tilt religious lunacy. Such blindness is now particularly unhelpful, given the hideous collision with Islamic certainty that is unfolding all around us.
Second, many religious moderates imagine, as you do, that there is some clear line of separation between extremist and moderate religion. But there isn't. Scripture itself remains a perpetual engine of extremism: because, while He may be many things, the God of the Bible and the Qur'an is not a moderate. Read scripture more closely and you do not find reasons for religious moderation; you find reasons to live like a proper religious maniac-to fear the fires of hell, to despise nonbelievers, to persecute homosexuals, etc. Of course, one can cherry-pick scripture and find reasons to love one's neighbor and turn the other cheek, but the truth is, the pickings are pretty slim, and the more fully one grants credence to these books, the more fully one will be committed to the view that infidels, heretics, and apostates are destined to be ground up in God's loving machinery of justice.
How does one "integrate doubt" into one's faith? By acknowledging just how dubious many of the claims of scripture are, and thereafter reading it selectively, bowdlerizing it if need be, and allowing its assertions about reality to be continually trumped by fresh insights-scientific ("You mean the world isn't 6000 years old? Yikes"), mathematical ("pi doesn't actually equal 3? All right, so what?"), and moral ("You mean, I shouldn't beat my slaves? I can't even keep slaves? Hmm"). Religious moderation is the result of not taking scripture all that seriously. So why not take these books less seriously still? Why not admit that they are just books, written by fallible human beings like ourselves? They were not, as your friend the pope would have it, "written wholly and entirely, with all their parts, at the dictation of the Holy Ghost." Needless to say, I believe you have given the Supreme Pontiff far too much credit as a champion of reason. The man believes that he is in possession of a magic book, entirely free from error. Here is the Vatican's position (from the Vatican website), in the words of Pope Leo XIII in Providentissimus Deus (his 1893 encyclical on the Study of Holy Scripture):
[I]t is absolutely wrong and forbidden, either to narrow inspiration to certain parts only of Holy Scripture, or to admit that the sacred writer has erred. For the system of those who, in order to rid themselves of these difficulties, do not hesitate to concede that divine inspiration regards the things of faith and morals, and nothing beyond, because (as they wrongly think) in a question of the truth or falsehood of a passage, we should consider not so much what God has said as the reason and purpose which He had in mind in saying it-this system cannot be tolerated. For all the books which the Church receives as sacred and canonical, are written wholly and entirely, with all their parts, at the dictation of the Holy Ghost; and so far is it from being possible that any error can co-exist with inspiration, that inspiration not only is essentially incompatible with error, but excludes and rejects it as absolutely and necessarily as it is impossible that God Himself, the supreme Truth, can utter that which is not true. This is the ancient and unchanging faith of the Church, solemnly defined in the Councils of Florence and of Trent, and finally confirmed and more expressly formulated by the Council of the Vatican. These are the words of the last: "The Books of the Old and New Testament, whole and entire, with all their parts, as enumerated in the decree of the same Council (Trent) and in the ancient Latin Vulgate, are to be received as sacred and canonical. And the Church holds them as sacred and canonical, not because, having been composed by human industry, they were afterwards approved by her authority; nor only because they contain revelation without error; but because, having been written under the inspiration of the Holy Ghost, they have God for their author." "