to read that book objectively and not start to question things (Tunesmith)

Tunesmith, I am unable to do both things at the same time. If I am reading a book objectively (that is in another state of mind than the one when I'm reading, say, a novel) then I start to question things.

By the way, McGrath is right. Myth is metaphor. It illustrates a point. Not factual. But true. (Don Firth)

No, Don, McGrath has been too careful to state that. He has just cited one of many meanings of 'myth'.
Another definition for instance is: "An ill-founded belief held uncritically by an interested group."

I'm not completely sure what Timothy Freke means when using the word 'myth', but he most certainly doesn't use the word in McGrath's definition.

The definition that may unite most of us goes like that: "A person or thing having only an unveryfiable existence"

Wolfgang