The myth-metaphor gospel

In response to D. Sutherland's letter in the Record: he espouses the thesis of Tom Harpur, author of The Pagan Christ, that Christianity is based primarily on myth, up to and including the Christ. Further, that Jesus is a metaphor for what might be God's grace. Also, that within this thesis, the future of Christianity is assured.
As I read of, listen to, and discuss with people who espouse this myth-metaphor gospel, I sense that they, in their searching, are creating and becoming another myth. They are becoming a metaphor for apostasy.
God bless us everyone!