So as I ask the question (see below, in boldface; I would greatly appreciate some feedback here), I realize I'm a gnat pestering a giant of Matthean scholarship. But here goes anyway: In an autobiographical moment, Betz reveals how he became so interested in the Sermon on the Mount:
When I was working on the commentary on Galatians I noticed the unusual number of parallel references, mostly of antithetical parallels, that kept coming up between Galatians and the Sermon on the Mount.3
Does anyone else find it ironic that Betz was steered into the Sermon on the Mount via Paul's letter to the Galatians, especially in light of his strong differentiation between the Christianity behind the Sermon and Pauline Christianity? To be sure, Betz refers to finding "antithetical parallels" between Galatians and the Sermon. But I can't shake the suspicion that Betz employs an unhelpful conceptualization, made influential by F. C. Baur and the Tübingen school, that opposes a "Pauline" Christianity with a "Jewish" Christianity. Certainly "Jewish" Christians could (and did) have problems with Paulinism. But the story of Pauline scholarship in the last quarter of the twentieth century is largely the story of scholars rediscovering that the opposite of the adjective Jewish is not Pauline.4 Betz is not unaware of this rediscovery, but I'm not sure how his reconstruction of Christian origins on the basis of Galatians and the Sermon can stand in light of it.
1 Klyne Snodgrass, "A Response to Hans Dieter Betz on the Sermon on the Mount," BR (1991), 88.
2 Hans Dieter Betz, The Sermon on the Mount: A Commentary on the Sermon on the Mount (Hermeneia; Minneapolis: Fortress Press, 1995).
3 Hans Dieter Betz, "The Sermon on the Mount: In Defense of a Hypothesis," BR (1991), 74. Betz refers to his commentary, Galatians: A Commentary of Paul's Letter to the Galatians (Hermeneia; Philadelphia: Fortress Press, 1979).
4 This is often referred to as "the Sanders Revolution" (in honor of E. P. Sanders) or, more popularly, "the New Perspective on Paul."