“For he himself is our peace, who has made the two groups one and has destroyed the barrier, the dividing wall of hostility, by setting aside in his flesh the law with its commands and regulations.”
Circumcision divided Jews and gentiles. Some in that “club” saw themselves as above others. But circumcision is a one-time thing, rather than an ongoing “heart” thing.
Paul often wrote letters (eg. Romans) addressing how we learn to live in a multicultural society. Christ, himself, brought peace to earth. If we are to live in peace, we should learn how to unite despite our differences.
Sadly, Christianity today is full of division. Something that flies in the face of Christ’s message and Paul’s teaching.