The Duet...

13 “Their throat is an open grave;
    they use their tongues to deceive.”
“The venom of asps is under their lips.”
14     “Their mouth is full of curses and bitterness.”
15 “Their feet are swift to shed blood;
16     in their paths are ruin and misery,
17 and the way of peace they have not known.”
18     “There is no fear of God before their eyes.”

19 Now we know that whatever the law says it speaks to those who are under the law, so that every mouth may be stopped, and the whole world may be held accountable to God. 20 For by works of the law no human being will be justified in his sight, since through the law comes knowledge of sin.

21 But now the righteousness of God has been manifested apart from the law, although the Law and the Prophets bear witness to it— 22 the righteousness of God through faith in Jesus Christ for all who believe. For there is no distinction: 23 for all have sinned and fall short of the glory of God, 24 and are justified by his grace as a gift, through the redemption that is in Christ Jesus, 25 whom God put forward as a propitiation by his blood, to be received by faith. This was to show God's righteousness, because in his divine forbearance he had passed over former sins. 26 It was to show his righteousness at the present time, so that he might be just and the justifier of the one who has faith in Jesus. (Romans 3)

As seen in the opening verses of the chapter, there is no favortism with God. All of us are sinners, Jews & Gentiles alike. The opening verses of this section can be sung by all, though in a painful sounding dissonance: out of our mouths and in our hearts is sin and the lack of the fear of God.  There is also a beautiful duet between the Law and prophets with the Gospel: all have sinned, but can be justified by grace through faith in Christ.  One is a terrible clashing in the ears and gnashing of teeth. The other is the most joyful song ever, blending Old Testament and New in one glorious duet: the song of the Redeemed.