This is speaking of jesus dying for our sins.
Jesus is the faith the scripture is referring to and,its also saying all can be saved not just
the lineage of moses who the promise was originally made to! This is also why the laws differ from the old treatment to the new!
BUT BEFORE FAITH CAME,
WE WERE KEPT UNDER THE LAW, SHUT UP UNTO THE FAITH WHICH SHOULD AFTERWARDS BE REVEALED.
WHEREFORE THE LAW WAS OUR SCHOOLMASTER TO BRING US UNTO CHRIST,
THAT WE MIGHT BE JUSTIFIED BY FAITH. BUT AFTER THAT FAITH IS COME,
WE ARE NO LONGER UNDER A SCHOOLMASTER. FOR YE ARE ALL THE CHILDREN OF GOD BY FAITH IN CHRIST JESUS.