How unlikely St Joseph is. He surely knew he was part of the Davidic line, but Bethlehem was then an unimportant village in Judea. He probably believed a Messiah would come, but he likely did not know he was the branch from which the Messiah would come. He was just an unimportant laborer, part of the class that Josephus said should listen in silence in the synagogue and never speak. And he never does speak. He does listen when God speaks and he immediately does what God says to do.