Fisherman: Yeah right. All the sworn oaths about him being related to Abraham and Judah and David and Solomon….were lies.
Well... yeah, aren't they? Mixing a bit of DNA to make him their heir seems like the most technical of technicalities. That lineage was not going to produce a god without the actual intervention of god. So the genealogy was not a scientific or medical record of any kind, it was showing the familial lines that led to the two people who would be allowed to serve as god's parents.