For John Spong to assert the ressurection as metaphor when the gospels are clearly historical narrative reveals a breathtaking depth of cognitive dissonance. In other words, he’s a God hating loon.
Spong is simply following modernist Bible scholarship, which has it that the Gospels are late compositions. The consensus among them is that except for Mark they were all composed after about 80 A.D. But that requires that we disregard all allusion to the destruction of the Temple as after the fact. I don’t see why we should.