Why Did God Create This One New Humanity?

In Ephesians 2 and 3 Paul talks about the difference between Jews and Gentiles before Christ. And yet through his death Christ breaks down that dividing wall of hostility between Jew and Gentile creating one new humanity in Christ. In other words, why did God create this one new humanity out of the two? It's so that when anyone looked at it, whether in heaven or on earth, they would see just how glorious Jesus is.