The wall, the shroud between Gentiles and Jews came down when Christ died for humanities' sins. He first came to the Jews the lost sheep of Israel. He was a leader for the prodigal sons who had grown away from their father. Jesus could not be contained only to the Jews, the Gentiles would be healed as well.
Matthew 15:26-27 (The Message)
26He said, "It's not right to take bread out of children's mouths and throw it to dogs."
27She was quick: "You're right, Master, but beggar dogs do get scraps from the master's table."