As regards the gospel, they are enemies for your sake. But as regards election, they are beloved for the sake of their forefathers. (ESV)
Did you ever have a family member that was just really hard to get along with? I am sure that there are very few people who could say that they always get along with everyone in their family all the time. In some respects the Apostle Paul is having to deal with a family feud between the Gentile Christians and the Jewish non-Christians.
The non-believing Jews are enemies of the Gospel. In the previous verses Paul has described a partial hardening of the hearts of the Jews. This does not mean that there are no Jewish converts to Christianity, but they are a small number. For the most part the Jews are acting like the older brother who cannot get along with his younger siblings.
In Acts 14:19, Luke writes of what happened to Paul as he preached the Gospel at the city of Lystra: "But Jews came from Antioch and Iconium, and having persuaded the crowds, they stoned Paul and dragged him out of the city, supposing that he was dead." Paul loved his Jewish brothers and sisters as his own family. They did not return the favor.
Paul knew that while many of the Jews had caused him great pain and suffering, they were still the beloved of God because they were related to the patriarchs of the faith; Abraham, Isaac, and Jacob. It was not easy for Paul. He was stoned, shipwrecked, beaten, and ultimately put to death at the hands of the Jews. In spite of all that, Paul demonstrated for us that we should love our enemies as brothers.
Who is it that gives you the hardest time in your life? A family member? Co-worker? Neighbor? Ask the Lord to love them like a brother. Perhaps they will see your love and come to Christ. Even if they do not you will honor the Lord by loving your enemy, just as Jesus, and Paul did.