Christianities versus Christianity

I think David Gushee gets it right:

I remember the first time it became crystal clear to me that there is no such thing as Christianity, but only competing Christianities. It was when I was working on my doctoral dissertation on Christians who rescued Jews during the Holocaust. During that time I attended a most remarkable conference in New York on hidden children of the Holocaust. This gathering brought together the now-grown adults who had hidden from the Nazis to survive. Some of these children were saved by Christian families.
The most memorable speaker for me was a hidden child, and now a sociologist, named Nechama Tec. A Polish Jew, she survived the war hiding with Christians. She was asked after her address whether it was Christianity that motivated her rescuers. Her unforgettable response went like this: “It wasn’t just any kind of Christianity that would motivate a rescuer. Only a certain kind of Christianity would lead someone to risk their lives for us.”
A certain kind of Christianity — the phrase stayed with me. It is enormously helpful. From hard experience, young Nechama Tec learned the difference between versions of Christianity that teach hatred of the religious/ethnic other and versions that teach sacrificial and inclusive love. Her very survival depended on being able to tell the difference between these competing Christianities and the people who embodied them.

Of course, this is what was in my mind when I wrote A New Kind of Christian and A New Kind of Christianity. It’s also at the heart of my upcoming book, the title of which will be released soon.
Gushee adds this important note, reflecting on recent tensions among Christians of competing Christianities and Islaams:

So the Christianity of “International Burn a Koran Day” exists. It is a sorry version of Christianity, but it exists. It must be defeated by better versions of Christianity. Maybe some progress has been made on that over the last week.
Could it also be that there is no such thing as “Islam,” but only competing versions of Islam? Could it be that those who are casually declaring that al Qaeda’s Islam just is Islam are about as accurate as those who would say that Terry Jones’ Christianity just is Christianity? Could it be that we need a moratorium on people who know nothing about the competing Muslim traditions making blanket declarations about the eternal nature of that religion?