Intent of the Law

Brothers and sisters, I speak in terms of human relations: even though it is only a man’s covenant, yet when it has been ratified, no one sets it aside or adds conditions to it.

What I am saying is this: the Law, which came 430 years later, does not invalidate a covenant previously ratified by God, so as to nullify the promise.

This is speaking allegorically, for these women are two covenants: one coming from Mount Sinai giving birth to children who are to be slaves; she is Hagar.