"And He has made known to us the mystery of His will according to His good pleasure, which He purposed in Christ as a plan for the fullness of time, to bring all things in heaven and earth together in Christ." Ephesians 1. 9-10
The apostle Paul is the "poster boy" of the Protestant reformation, which presented late medieval Catholicism as being like 1st century Judaism in its legalism. "Justification by faith alone" (sola fide) became the battle-cry of the new movement which spawned the Protestant family of churches. For the required biblical mandate, Protestant theologians homed in on Paul's letters to the Romans and Galatians, which are all about justification through faith rather than good works or observing the Jewish law, and thus gave the impression that this expressed the heart of Paul's own convictions.
More recently, however, scholars have argued for a re-interpretation of Paul, on the basis that he has been misrepresented. When understood from his own perspective, as a 1st century Jew whose life was transformed by encountering the risen Jesus, Paul is primarily interested in the significance of Jesus being Messiah for all nations; that his unique fulfilment of the law broke the power of Torah, which had driven a wedge between God and his people and erected a ring-fence separating Jews from the rest of the world. Now everybody has access to God and may be welcomed into the Kingdom - through faith in Jesus, as the means rather than the end.
Reconsidering the teaching of Paul in this way was popularised by scholar-bishop NT (Tom) Wright, though credit for its initiation goes to fellow academics EP Sanders and JG Dunn. But if you google the "new perspective on Paul", you are more likely to discover what it isn't than what it is! That is because, like the Protestant reformation it implicitly criticises, the "new perspective" has spawned many branches, most of which disagree. But all do at least share the essential conviction that it is vital to read the scriptural authors on their own terms because that must surely take us as close as we can get to the voice of the Spirit, which instructed them to write in the first place.