The righteousness of God is a notoriously complicated question in the study of Paul. Paul’s use of righteousness terminology in Romans is mystifyingly polyvalent, and there is good evidence that he has multiple meanings in play throughout the letter, and often multiple meanings in play in each individual use of words from the δικαι- group. While some recognition has been given to how Paul’s semantic assumptions arise from his appropriation of the correlate terminology in the Hebrew Bible (and their translations in the LXX), insufficient weight has been given to how righteousness language is developed in Isaiah, and how that development gives a fruitful vantage point to understanding and integrating Paul’s far-flung associations attached to righteousness. Specifically, Isaiah develops a sense of God’s righteousness as synonymous with God’s salvation (e.g. Isa 51:1-8), and this salvific righteousness of God creates the moral righteousness practiced by his people. This is a critical element in understanding how and why Paul connects God’s saving agency as a revelation of his righteousness with the realization of his righteousness in the lives of christian communities in Rome.