Separated from each other
“Therefore, remember that formerly you who are Gentiles by birth and called “uncircumcised” by those who call themselves “the circumcision” (which is done in the body by human hands).
The reality of human separation from each other goes back to the fall in Genesis 3. That reality is however still with us today as we see in racial, tribal and national hatred in our times. Human beings have hated each other and gone to great lengths to demonstrate it.
In this passage, Paul calls Ephesian believers to remember that they, were gentiles by birth and were called ‘uncircumcised’. The Jews had a very low opinion of Gentiles and viewed them as the lowest of the law. In his commentary of Ephesians, John Stott quotes William Barclay to express the depth of the separation.
‘The Jew had an immense contempt for the Gentile. The Gentiles, said the Jews, were created by God to be fuel for the fires of hell. God, they said, loves only Israel of all the nations that he had made …. It was not even lawful to render help to a gentile mother in her hour of sorest need, for that would simply be to bring another Gentile into the world. Until Christ came, the Gentiles were an object of contempt to the Jews. The barrier between them was absolute. If a Jewish boy married a Gentile girl, or if a Jewish girl married a Gentile boy, the funeral of that Jewish boy or girl was carried out. Such contact with a Gentile was the equivalent of death. 
But the hatred went both ways. The Gentile treated the Jews with similar if not more contempt. The Jews have been hated in much of human History having suffered genocides perhaps more than any other people in history in what is more recently called anti-Semitism.
But the division goes beyond Jews and Gentiles. All of humanity is broken by sin all the way from Genesis 3. We see evidence of that in wars, The transatlantic slave trade of the 16th and 17th Century, The Rwandese Genocide of 1994 where nearly a million Tutsis and moderate Hutus were killed, The tribal clashes in our own country in 1992, 1997 and 2007 and in many other ways and places. We are broken as a society and almost always at war with each other.
If the imagery of the Jew-Gentile separation did not strike you, Paul uses the second imagery of the derogatory term ‘uncircumcised’. This term pointed to the uncultured outsiders who did not bear the covenant mark of membership in God’s family. Closer home, the idea of being uncircumcised is derogatory in most cultures. It is a term used to demean, despise, dehumanize, reject and exclude others. Such was your state and mine – hating and being hated.
Paul wants us to appreciate how wide and deep this division is because unless we appreciate the extent of the rot, we might not fully appreciate Christ’s unifying work on the cross.
 Stott, JRW The Message of Ephesians,1979 Nottingham, UK, Intervarsity Press. Page 91