I am sure at this point in Paul's letter to the Romans, the Jews were feeling pretty beaten up. Paul spent the last few verses revealing to them that they had misunderstood God covenant with them. They were operating under the assumption that because they were the natural descendants of Abraham, they were heirs to the promise.
However, Paul reveals to us at the end of Romans 2 and also in Galatians 3, that the promise was not many descendants but One descendant. "The promises were spoken to Abraham and to his seed. The Scripture does not say "and to seeds," meaning many people, but "and to your seed," meaning one person, who is Christ. " ( Galatians 3:16 ) So we can conclude that no one has ever become a heir of God's promise by natural birth as the Jews assumed. Before Christ, Old Testament saints were justified by faith in God's promised Messiah. After Jesus, we are justified through Faith in Christ. Heirs of the promise are those who are of the spiritual seed of Abraham, and are justified by faith. ( Romans 4:16 )
So the natural question arises...what advantage is there in being a Jew? Paul just proved to them that they were guilty before God, just like the Gentiles. Then revealed to them that being born into this nationality did not make them heirs of the promises. It was only through faith in the Jesus Christ, which gave them circumcision of the heart through the Spirit, not of the flesh. Everything that the Jews held onto as being a people separated apart for God had been utterly shattered with Paul's letter, so one needs the answer for, the benefit, profit and gain in being a Jew.
Fortunate for us, Paul gives us the answer in verse 2. Being a Jew profits "Much in every way! First of all, they have been entrusted with the very words of God." ( Romans 3:2 ). God had trusted them with His spoken and written word. Not only did he give them intuitive knowledge of himself like the rest of creation, He gave them the oracles of God. They were literally given the intension and utterances of our Heavenly Father. This profited them much in every way!
God places a huge importance on His Word. Psalm 138:2 says, "for thou hast magnified thy word above all thy name." (KVJ) on the other hand, Philippians 2 says "That at the name of Jesus every knee should bow, of things in heaven, and things in earth, and things under the earth; And that every tongue should confess that Jesus Christ is Lord, to the glory of God the Father. " ( Philippians 2:10-11 ) The Bible says that at the name of Jesus, everything will come into submission to Him, and then that God magnifies his Word above His name. Therefore, since the Jews were entrusted with the Words of God, they retained a favorable position with God right from the very beginning.
Today, we also are blessed through the Jewish race because we also the Word of God. We have access to these words that bring life and health to our bodies and nourishment to our bones ( Proverbs 3:8 ) So today we can rejoice in God's graciousness with mankind because of Christ. And rejoice that He provided us with everything pertaining to life and godliness through His Word.