Who Are Our Brothers and Sisters in Christ?

Romans 9:1-5 (NRSV) I am speaking the truth in Christ—I am not lying; my conscience confirms it by the Holy Spirit. I have great sorrow and unceasing anguish in my heart. For I could wish that I myself were accursed and cut off from Christ for the sake of my own brothers and sisters, my own flesh and blood. They are Israelites, and to them belong the adoption, the glory, the covenants, the giving of the law, the worship, and the promises; to them belong the patriarchs, and from them, according to the flesh, comes the Christ, who is over all, God blessed forever. Amen.