When I re-read my reply, I found out that due to the structure of my response, I might be misinterpreted. This is a more clear response from me:
I don’t agree with the commentary because the Judaizers relied upon faith AND the works of the Law, just like Catholic soteriology would have us believe about the Jews living under the Old Covenant.
Now, because of this, Paul has no basis for quoting Deuteronomy 27, in which he claims that the Jews could not be justified through obedience to the Law and faith in Christ.
I will try to get to the heart of the answer you’re looking for so tell me if I’m on track with what you’re saying.
The Jews believed that you had to not only believe in God but also adhere to the laws that Moses gave them. Their adherence to strict Jewish Law is what kept them in favor with God, though many times there was no adherence to the law. Christians, on the other hand, rely on God Himself, who dwells within us, to turn our hearts and minds into something pleasing to God. Are we still on the same track?
If so, then here’s the rest of it. Because our good deeds come from God and the indwelling of the Holy Spirit within us, it sets us apart from the Jews who relied on their own ability to adhere to Jewish Law.
St. Paul, in Galatians 3:10, references Deuteronomy 27:26 so as to make a comparison between the Jews of the Old Covenant, who relied on their own ability to follow the Laws of Moses, as opposed to the followers of the New Covenant who relied on Christ and the indwelling of the Holy Spirit to change their hearts from evil to good. Remember, the very next verse of St. Paul’s letter states “Now it is evident that no man is justified before God by the law; for ‘He who through faith is righteous shall live’” (Galatians 3:11). Keep in mind that even the Jews, who had no faith in their God, were not following the Law of Moses since that would be a violation of the first three Commandments. In that respect, St. Paul could have been clarifying for us that even the ones who called themselves Jews were not really Jewish if they did not believe in God, as that would violate the Commandments.
Christ dwells in us as we dwell in Him, since the body is for the Lord and the Lord for the body (1 Co. 6:13). That is the core idea of faith. The ones who called themselves Jews but did not believe, just followed the Law without faith, and that, as St. Paul reminds in in Gal. 3:11 is pointless, wheteher you are of the Old Covenant or the New Covenant. This is the reason why God became enraged with worthless sacrifices, as people just sacrificed to appease their own customs, not necessarily out of sorrowful regret for their sins.
One more thing to add to this, is that the Catholic Church for 2000 years has not taught any kind of a “works” salvation. The Church believes that it is not of our own doing but that of God that we become worthy of the promises of Christ. Having said that, we put into context the words of James who says “So faith by itself, if it has no works, is dead” (James 2:17). This applies to the Jews as well as the Gentiles, as God asks us to love Him just as He loves us. If we do that, we will abide in His will and the Holy Spirit will dwell in us.
If I understood your comment correctly, than this will help to clarify the Catholic position a little. I’m very happy to have this discussion with you and if I can help in any other way please don’t hesitate. I look forward to your response.