Three Hebrew root letters, SDQ, without vowels, have three main interpretations.
The common reading "Sedeq" or "Sedaqa" reads "dikiaosyne" (noun) in Greek, meaning both a forensic acquittal, and a moral standing (48). NT Wright uses Dikiaosyne quite a bit in his 2013 "Paul and the Faithfulness of God". Doug Moo calls NT Wright's school "covenant-faithful" righteousness - from Genesis 15:6 where God considers Abraham's faith to be equivalent to his discharge of all the obligations incumbent upon him (54). God's righteousness, expressed in Isaiah 46-55 is not just moral but also an act of justice and vindication. Faithfulnes of God as the book title tells us where here Wright's locus classicus is. Isaiah 50:8 is reprised in Romans 8:33: Who is my accuser, let him confront me! (53). Dikaiosyne appears only 4 times in Galatians.
DikiaoO, (verb) from "Sadiq" is found fewer times in Galatians. It is what all lawyers want to hear. "Not Guilty". Not quite the same as Proven Innocent as with "Sedaqa". All you need is to have faith, which I think is Martin Luther's reading of Romans 1:17, the entry grade John 3:16, or what Dietrich Bonhoeffer coins "cheap grace".
Dikaios, (adjective) appears only once in Galatians, in Paul's quotation of Habakkuk 2:4 at Galatians 3:11. "Saddiq" is full measure of OT perfectionism. Jesus, the ultimate Pharisee, would qualify. I do not think Paul felt he met that standard (Romans 3:23).
I am grateful to Douglas Moo for teasing out the nuances of Hebrew, and for drawing from scholars like Ziesler and Seifrid, although workhorses like Richard Longenecker are also referenced. Those who wish the Rt Hon Bishop Wright to stay in an asylum for his 2 step justification, may also wish to look up Douglas Moo's TIME of JUSTIFICATION (60). Paul insists that people are justified by faith is the sense that it is "How you get saved". Moo (he is not Korean, as the name suggests) argues that Paul left justification "timeless" and "indetermined". Justification for a Christian is presumed. But the situation in Galatia requires that Paul emphasize how this "righteousness" is to be maintained, and how they can be found "right" in the judgement. As Ridderbos puts it, Future Righteousnes has already been revealed. Paul responded to false teachers who claim that vindication is only for Israel, and can only be experienced by gentiles taking on Torah rituals. Moo argues Paul had to dismiss the need for Galatians to supplement their faith with torah observances. For Paul reads salvation from the epochal significance of the cross and insists that faith and faith alone (accompanied by transformation by the Spirit) maintains one's relationship with Christ and the People of God.
Has Moo back paddled? I went back to his 1996 NICNT Romans Chapter 12 and was assured he had not. Romans 12-15 was not an add-on (744, infra) and this was Paul's grandest exposition of the gospel. The power of God's righteousness is unleashed. Deliverance from the power of Sin is inseparable from deliverance from its Penalty (Romans 6). Union with Christ provides both. The transformed life is not a "second step", but an indispensable dimension of the gospel itself. What God has Given us (Romans 1-11) gives way to what we are to give to God. The indicative parts of the gospel gives way to praxis, from theory to practice. One can be forgiven for thinking that NT Wright was inspired by this kind of sentiment exposited by Douglas Moo (as early as 1996). Very James 2:17, Faith and Works being two sides of the same coin.
There is a proofreading error on page 48 which will make the American rend his shirt. "The verb DikaioO occurs 15 times in the 7,111 verses of Romans, compared with the 8 occurrences in the 2,230 verses of Galatians..." I have Felix Just's table with me, which says Romans 433 verses and Galatians 149 verses. Now, in that same table is Hebrews 4,953 words. Knock out the last verse of Galatians, 6:18, and follow on with Hebrews 1:1, as in the page numbered Codex Vaticanus, one can entertain Hebrews starting right after Galatians. Luke must have told Paul to cool it, and to remind the Galatians of the importance of Israel's ancestors, to smooth ruffled feathers. Strain the theology of Hebrews through the sieve of Galatian Praxis and we get 2230 + 4953 words = 7183 words, and hey presto, we have ourselves an Ur-Romans (c 7,111 words) or proto-Romans. That is my humble suggestion for the missing author of Hebrews. It was Paul's sentiments, with Luke's erudite Greek. Doug Moo thinks it is someone like Apollos. An appropriate shift in the Athanasian canon can explain why NT Wright is constantly digging into Israel's past, and why a back end of the bible specialist, like Doug Moo has advanced so far front to Romans and Galatians.
If you had around $30 to spend on a theological study (most in this class come in multiples of $30), this is one priority. There are not too many exquisitely bound Hard Covers at this price range. A stately reference for all time. Read it for style. Read it for its profound analyses. Read it, I dare claim, for enjoyment. Among the writings of Paul, none is as important and as difficult to understand (William Baird).
Doug Moo sifts through sinking sand all around the central tenets of Galatians, so read it, if only to reinforce that faith which is grounded on the most solid rock of all.