John Edward doesn't threaten anyone's religion. But people's religious beliefs do talk about John Edward. John Edward is not threatening christianity. He is defined within christian beliefs. And that is why they are so adamant about it.
Myself... I always get a kick out of people asking for "proof" about philosophy or beliefs. I'm sure you believe many things that you can't "prove" scientifically as well. We all do. Personally.... I just accept someone saying such and such is a fact, as a statement that what they believe philosophically, they belive very strongly... to the point it is a fact for them. I know I'm that way myself about a lot of things.
So when I tell you "everything has a religious aspect to it. Everything." Just accept my statement for what it is. A fact for me, and a point of contention for you. The thing I've noticed about most facts... is that people believe the ones they want to believe. And they dispute until the sun goes down the ones they don't want to believe.