“The problem of the proper interpretation of dikaiosyne theou in Romans has been one of the hotly debated issues in New Testament studies over the past generation, but rare is the critic who even considers the possibility of interpreting Paul’s ‘righteousness of God’ language against the background of the LXX. Learned scholars have argued bitterly whether dikaiosyne theou was a technical term in Jewish apocalyptic thought, as attested especially in the Qumran texts, or whether it was a new creation of Paul’s theological genius, without ever observing that the very Old Testament texts quoted by Paul in Romans 3 already introduce the idea of God’s righteousness. This remarkable oversight illustrates the power of hermeneutical conventions in shaping a community’s reading of its canonical texts. The Reformation theme of justification by faith has so obsessed generations of readers (Protestant readers, at least) that they have set Law and gospel in simplistic antithesis, ignoring the internal signs of coherence in Rom. 3:1-26; consequently, they have failed to see that Paul’s argument is primarily an argument about theodicy, not about soteriology. The driving question in Romans is not ‘How can I find a gracious God?’ but ‘How can we trust in this allegedly gracious God if he abandons his promises to Israel?’ Christian caricatures of the Old Testament have made it difficult for belated generations of Gentile readers to grasp Paul’s passion for asserting the continuity of his gospel with the message of the Law and the Prophets. By following the echoes of Psalm 143, however, we can rediscover the scriptural idea of God’s saving justice at the foundation of Paul’s argument in Romans.
That is why Paul insists (Rom. 3:31) that his gospel does not annihilate the Law but establishes it. How so? First of all, Paul’s proclamation presents the righteousness of God not as some unheard-of soteriological novelty but as the manifestation of a truth attested by Scripture from the first. When he says that his message confirms the Law, he refers not to the specific commandments of the Pentateuch but to the witness of Scripture, read as a narrative about God’s gracious election of a people. That is why the Abraham story becomes for Paul the crucial test case. If he can show, as he sets out to do in Romans 4, that the story of Abraham supports his reading of God’s Gentile-embracing grace, then he will have demonstrated, to his own satisfaction at least, the unity of gospel and Law.”
-Richard B. Hays, Echoes of Scripture in the Letters of Paul