A Jewish missionary who preached the Messiah, not the founder of Christianity

“Paul the Jewish Theologian” fundamentally reconstructs the image of Paul we are familiar with.
Matthew Thiessen, a prominent New Testament scholar today, goes beyond the traditional view of Paul as a “Jewish convert to Christianity” or “founder of Christian theology,” portraying him as a man who confessed Jesus as the Messiah while remaining a faithful Jew until the day he died.
According to him, Paul was not a person who broke away from Judaism, but a missionary who proclaimed within Judaism that Gentiles could also be included as God's people through the Messiah Jesus.

This book not only sheds new light on Paul's identity, but also reinterprets core themes of Paul's theology—the law, righteousness, circumcision, mission to the Gentiles, the Holy Spirit, Jesus the Messiah, and resurrection—from a "Jewish imagination."
The author proposes a framework for interpretation called “Paul in Judaism,” which can be called a “fourth perspective,” going beyond the hermeneutical trends that led to Luther’s antinomianism, the “new perspective” beginning with Sanders, and the apocalyptic interpretation.

The absence of the word “Christian” in Paul’s writings can be explained by one of two reasons:
First, Paul may not have used this term because he did not know it.
Most scholars do not believe that Acts or 1 Peter were written during Paul's lifetime.
Therefore, it may be anachronistic to use the terms “Christian” or “Christianity” in reference to Paul or the groups he organized and wrote to. Second, and perhaps more interestingly, the term “Christian” was used roughly several decades before Acts and 1 Peter, and Paul may have been aware of it, but he may not have used it consciously.
If that's true, why did Paul do that? Did he dislike the term? If so, then applying it to Paul and his earliest readers is not only anachronistic, but also non-Pauline and even antithetical to his thinking.
--- From "Chapter 1: Making Paul a Strange Person Again"

Judaism believed nothing about Gentiles and salvation.
Meanwhile, Jews had various beliefs about Gentiles.
These various beliefs sometimes clashed and conflicted with each other.
And these differences also created discord between individual Jews and rival groups.
However, these diverse beliefs fall within the larger religious tradition we now call Judaism.
As we approach the Pauline epistles as modern readers and observe the conflicts that arise between Paul and others over exactly how Gentiles should relate to Israel's God, Israel, and Israel's law, we see a unique transformation and expansion of a much larger dialogue that the Jews, who received God's oracles and law under the conviction that they were God's chosen people, encountered in a Mediterranean world quite different from their own.
--- From "Chapter 3 Judaism Does Not Believe in Anything"

But the strongest external evidence that Paul intended to describe only Gentiles in this passage is actually found in his letter to the Ephesians.
The author of this letter—either Paul or one of his early followers—explicitly describes the fallen condition of the Gentiles who do not follow the Messiah:
“From now on, do not walk as the Gentiles do, in the futility of their minds.
Their understanding is darkened, and they are alienated from the life of God because of the ignorance that is in them, because of the hardening of their hearts.
“They became callous and gave themselves over to sensuality, to practice all kinds of impurity with greediness” (4:17-19).
--- From "Chapter 5: The Foreigner Problem"

Paul's messianic understanding is based on his self-understanding as a messenger of the gospel and a thorough understanding of what the God of Israel is doing now to redeem the world, including the Gentiles.
However, Paul understands this messianic idea within the broader context of God's dealings with Abraham, the ancestor of Israel.
In Galatians, Paul makes a claim that will frustrate or confuse many readers (3:16).
He says that God made a series of promises to both Abraham and Abraham's seed (Greek, sperma).
(A similar argument can be found in Romans 4.) He then makes a seemingly grammatically far-fetched argument, noting that the Jewish scriptures say “seed” (sperma) instead of “seeds” (spermata).
Paul argues, based on the singular noun, that the seed of Abraham refers only to one specific individual, not to all of Abraham's descendants.
Who is he? He is the Messiah.

--- From "Chapter 6: Jesus the Messiah"

Paul does not say that he is interpreting Genesis allegorically.
Instead, he argues that the Abrahamic narrative itself is an allegory. The distinction is important.
It's the difference between treating a historical work about the civil rights movement as an allegory about Jesus and treating John Bunyan's Pilgrim's Progress and George Orwell's Animal Farm as allegories.
In the former case, it is up to the reader to interpret it as an allegory.
In the latter case, the allegory is what the author intended, and the reader must accurately decipher the original intent of the allegory.
Paul argues that the Abraham narrative was originally written as an allegory.
In other words, the original intention of the Abrahamic narrative was to provide a story of Abraham and his sons that originally contained allegorical meaning.
And in Galatians 4:21-31, Paul wants to show his readers what this original meaning was and how it now applies to their present lives.
“Allegory” (all?goria) had this general meaning in Paul’s time, as we see in the works of Greco-Roman writers such as Heraclitus and Tryphon, and Jewish writers such as Josephus and Philo.
Allegory was a literary device used by the author, not an external interpretive strategy that later readers would apply to non-allergic texts.
--- From "Chapter 7: The Problem of Foreigners and Plastic Surgery"

So when Paul spoke of pneuma, he was speaking not only within the context of the Greek translation of the Jewish scriptures, but also within the intellectual context of the time, where pneuma was considered the highest substance in the universe.
In other words, unless Paul intended to convey a completely different meaning, his readers would have understood pneuma in the sense commonly used by those around them, namely, to refer to eternal and divine substance.
We don't know exactly what Paul was thinking, but I think if he was going to use the term in a way that was completely different from what most people around him meant—and if he wasn't a very awkward communicator—he would have been well aware that he had to be clear about what he meant.
Otherwise, he would have inevitably caused misunderstandings.
--- From "Chapter 8: Gene Therapy of Pneuma"

When we read 1 Corinthians 15, problems are bound to arise if modern astrophysics is involved.
Since most of us (perhaps all of us) make a clear distinction between the material and spiritual realms, when Paul uses the term “spiritual,” we might assume he means something immaterial. The NRSV translation of 1 Corinthians 15:44 distinguishes between the first body that is sown and the second body that comes from the seed that is sown.
“It is sown a physical body, it is raised a spiritual body.
If there is a physical body, there is also a spiritual body.” There are at least two problems with this translation.
First, the Greek word translated “physical” is “psychikos,” which does not mean body, but is rather related to the word “psyche,” which means soul.
So, although Paul is referring to a material body, that is not why he distinguishes between the two.
Rather, he alludes to Genesis 2:7, which says that God created man from the dust of the ground into a living soul (eis psych?nz?san).
Unlike this original “soul-like” (psychikos) body, the resurrection body will be a pneuma body.
Second, I prefer the term "pneuma" over "spiritual" because it distances modern readers from the inference that the spiritual is incompatible with the material/physical. (For example, how often have you heard that we should be grateful for spiritual blessings rather than material ones?)

--- From "Chapter 11: Resurrection as the Climax of the Second Coming of the Messiah"