Science can come up with parthenogenesis, but then the virgin Mary would have had a girl, Jesusita, or Emmanuelita, or something like that.

In this natural Universe, run by Universal Law, which you can call "God" if you wish, there is no Virgin Birth. Not even God can break the rules he set up. The people back then had no understanding of scientific principles and substituted Myth in its place. Probably because "God" has never told anyone back then what the science behind his creation was. He left it to us to figure it out.

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