I think that the discrepancies between Gospel narratives are interesting, especially in the Nativity segment. Luke and Matthew, although they used the same Q document and Mark for their basis, have different points stressed in their rendition. For example, only Matthew had the story of the Magi visiting, while only Luke had the explanation of why Mary and Joseph were going to Bethlehem. These writers were only human, and these differences show that neither writer knew the story in its entirety.