008: Connecting both units in Matthew chapter 1 (5 mothers)

This episode is about what connects the first unit and the second unit
in what we usually call Matthew chapter one, as if they might be
intended to function together as a single, whole as a single unit? It's
very easy to treat them separately as two distinct literary units. But how are they meant to be connected together as a single unit?  

And what
about Mary? Why does Mary appears in both units? Somehow Marry seems to
be connected back to the earlier references to four previous mothers in
the genealogy. But what is the connection? 

This episode won't be about
unpacking the pattern just looking at, what kind of connection it is
that we find in Matthew chapter one between the two units?