Matthew P. Larsen is asking for an explanation of Galatians 3:10 in light of the “old” and “new” perspectives on Paul. He asks three specific questions:
(1) How does the sentence Ὅσοι γὰρ ἐξ ἔργων νόμου εἰσίν, ὑπὸ κατάραν εἰσίν explain (γὰρ) Paul’s claim in Gal 3.6–9?
(2) In what sense does the citation γέγραπται γὰρ ὅτι ἐπικατάρατος πᾶς ὃς οὐκ ἐμμένει πᾶσιν τοῖς γεγραμμένοις ἐν τῷ βιβλίῳ τοῦ νόμου τοῦ ποιῆσαι αὐτά explain Paul’s claim that those out of the works of the law are under a curse?
(3) What mindset or activity was Paul primarily combating in Galatia in this verse?
So far James McGrath has responded. Here are my thoughts on these verses without referring to new and old categories.
1. Paul’s claim in 3:6-9 is that Abraham was saved by believing God, not by following any particular rules (Law). Those who want to be like Abraham need to live according to faith, not law. God’s proclamation to Abraham saw the Gentiles being justified by faith, not Law. If you (Galatians) want to be blessed like Abraham (and who doesn’t want that?) you had better rely on the same method he did – faith. He then makes the point in 3:10f and following that the Law brings not justification or blessing but curse and death.
2. He quotes Deut 27:26 to back up this statement. It has been debated how Deuteronomy relates to his point but it is obvious that Paul believed it supports his contention. His point is that the Law is designed to show who is cursed, not who is righteous. This statement in Deut concludes a section of sins with the statement “Cursed is anyone who does not uphold the words of this law by carrying them out.” It says nothing about “Blessed and righteous is the person who does uphold the words of this law.” This is made clearer with 3:19. Paul then contrasts this curse with a positive statement about being righteous, Hab 2:4 which states that the righteous shall live by faith (Gal 3:11).
3. Paul was combating the advocacy that Gentiles obey the Law in order to live righteously. The reason the agitators were so successful is that people naturally desire rules to live by. It is like in Lk 10:29 when the “lawyer” sought to justify himself by demonstrating that he had fulfilled the law’s requirement to love God and neighbour. Jesus soundly rebuked him with the parable of the good Samaritan. Paul is rejecting a similar attitude in Galatia. Justification comes by faith and results in walking in the Spirit and exhibiting the fruit of the Spirit, living by the Law results in slavery to rules that only reveal human sinfulness and ultimately lead to avoiding the appearance of evil such as listed in 5:19ff but does not change a heart of sin.
I know I have given a much longer answer than Dr. McGrath but I hope you find it concise enough and helpful.