Romans 9:3

"I could wish" introduces a wish that God would not possibly grant (Romans 8:35). Nevertheless it was a sincere wish. Paul had given up many things for the salvation of others (Philippians 3:8). Moses voiced a similar self-sacrificing wish for the Israelites’ salvation (Exodus 32:30-35). Paul’s brethren here were not his spiritual but his racial brothers and sisters. Even though he was "the apostle to the Gentiles" he still took pleasure in being a Jew.