Today’s Gospel gives the genealogy of Joseph, the purported father of Jesus. The Hebrew word for such a genealogy was toledoth, and something we must know about their toledoths is that they were not expected to be at all accurate listings. In a similar toledoth in Luke’s Gpspel there are forty generations between David and Joseph, while here there are only twenty-eight; and the names are mostly different.
What’s more, the time lapses are all wrong. For the eight hundred years between Abraham and David there are fourteen. For the four hundred years between David and the captivity there are fourteen generations. For the six hundred years between the captivity and Joseph there are fourteen generations.
It might be that Matthew was playing with an old superstition about numbers. Three fourteens is six sevens. That has Jesus starting a seventh seven which is a position only for one with a heavenly destiny.
All through his Gospel Matthew stuck to his purpose in writing his Gospel which was to show that mixing with non-Jews did not make Jesus unclean. In this toledoth he gets that message across by putting into his list three non-Jewish women: Tamar, Ruth, and Bathsheba. They were direct ancesters of the simon-pure King David.