I'm reading Baylor University sociologist George Yancey's and University of Georgia sociologist of religion Ashlee Quosigk's One Faith No Longer: The Transformation of Christianity in Red and Blue America. One of Yancey's theses is:
"Progressive Christians and conservative Christians have diverged so much in their core values that they ought at this point to be thought of as practitioners of two separate religions." (p. ix)
For my support of this see my recent book Deconstructing Progressive Christianity.
