The rhetoric and teaching methods of Jesus and Paul are best understood as part of the emerging rabbinic movement that would come to dominate Judaism after the destruction of the second temple. Like the Pharisees – the contemporaries of Jesus and Paul and the predecessors of the post-temple rabbis – both Jesus and Paul engaged in public Torah interpretation and controversy.
Jesus' disagreements with his opponents did not mean he rejected Torah obligations. They meant exactly the opposite. Jesus actively engaged in the interpretive debates about Torah interpretation between the early rabbinic schools of Hillel and Shammai – sometimes agreeing with one, sometimes the other, and sometimes challenging both with his own fresh application of the Torah to the challenges of the day. Many sayings of Jesus are halakhic statements that amend or modify traditional Torah precepts to conform to contemporary conditions. The collected sayings of Jesus in Matthew's "Sermon on the Mount" are quite simply the "Torah according to Jesus" – comparable to the collected Torah interpretations of other first century rabbis. Jesus ethics and eschatology only make sense inside second temple Judaism.
Paul – a Pharisee probably of the house of Shammai – never rejected his Jewish roots, education, or affiliation after his "conversion" to Christ. Although his Jewish worldview was radically reordered by the resurrection of Jesus and its eschatological implications, Paul remain a student of the Hebrew scriptures. His letters are replete with appeals to authoritative scriptural references. It appears that he remained Torah observant until his death – even though he embraced the prophetic role of "apostle to the Gentiles." Paul's "rabbinic" rhetoric is on display in the lively "debates" with his opponents in his letters.
Unlike Jesus, Paul seldom argued with Jewish scholars about the interpretation of Torah. Rather, his rhetorical flourishes were reserved for those who attacked the basic premise of his mission: the inclusion of Gentiles as "Gentiles" (with no Torah demand) in the end time people of God. Paul's opponents were perhaps Jews who demanded a proselyte conversion to Judaism before Gentile eligibility for inclusion into God's people. More likely, these opponents were Gentile proselytes who had themselves already taken on Torah obligation and felt that their fellow Gentile must follow the same path into God's end time community. Whichever may be the case, Paul wielded the Hebrew scriptures and rabbinic forms of rhetoric as weapons in the wars with those who would deny the validity of his mission to the Gentiles.