McGrath: Once again you refuse to properly argue for the use of hypothetical sources apparently underlying the Gospels that are necessary since you interpret Paul with Gospel tainted lenses and the Gospels themselves, as you know, are very problematic texts. If someone can explain to me why this is justified, and why we should prefer McGrath's or Ehrman's or Casey's hypothetical sources, and not a Christian apologist's or fringe mythicist's hypothetical sources, I might finally be persuaded.