Think about what that means for a moment. Paul is saying that Christ has broken down the defenses, the protections, that divided Jew from Gentile, nation from nation. This is no cheap metaphor. A city without a wall, or a Temple without a wall, was vulnerable. It was naked. Yet Paul here is saying that what has happened in Christ Jesus and in the preaching of his Gospel has broken down the wall that kept Jew and Gentile in hostility to each other. The people who share in the gifts of his body and blood and who receive his triumph over sin and death by faith, those people are no longer divided into insiders and outsiders, into the safe and the abandoned, into the privileged and the excluded.