In verse 1-2, Paul explains the advantage of the Jew to be the oracles of God; the words as recorded in the bible; the very thing people today regard with suspicion.
'What advantage then hath the Jew? Or what profit is there of circumcision? Much every way, chiefly because that unto them were committed the oracles of God.' We have access to the same words, which in chapter 3, conclude the following advantages:
that 'we are justified freely by his grace through the redemption that is in Christ Jesus.' Romans 3: 24
that 'God declares through faith in his blood his righteousness for the remission of sins.' Romans 3: 25
that 'a man is justified by faith without the deeds of the law.' Romans 3: 28
Paul was well acquainted with unbelief and argues, 'For what if some did not believe? shall their unbelief make the faith of God without effect?God forbid: yea, let God be true, but every man a liar.' Romans 3: 3-4
Why should we dispute the overwhelming evidence of what God reveals through the writings of Paul? Though the Jews had the words or oracles of God, they did not use them to showcase the fulfillment of the law in Jesus, nor did they receive grace through faith in his blood. They have annulled their advantage.
So it is with those who refuse the advantage of the biblical word of God.