The most recent issue of Catholic Biblical Quarterly has the following article:
Jerome H. Neyrey. "Syncrisis and Encomium: Reading Hebrews through Greek Rhetoric." Catholic Biblical Quarterly 82.2 (April 2020): 276–99.
Abstract: "Although the use of rhetoric to interpret NT texts, even Hebrews, is hardly new, here I employ an unfamiliar, and so unused source of Greco-Roman rhetoric, the progymnasmata (preliminary rhetorical exercises). They provide excellent examples of genres that form the skeleton and substance of the argument in Hebrews." These progymnasmata consisted of twelve to sixteen exercises of increasing difficulty, among which I focus on "comparison" (σύγκρισις) and "encomium" (ἐγκώμιον). Progymnastic rhetoric states that "comparison" are made out of the "headings' of the "encomium." Thus, one comparison is in fact two encomia, for example, Jesus and Israelite priests, each figure described according to traditional encomiastic patterns."
Neyrey claims that hardly anyone has applied the progymnastic exercises of encomium and syncrisis to the Book of Hebrews. He only cites C. F. Evans' slender monograph, The Theology of Rhetoric: The Epistle to the Hebrews. In fact, I deal at length with the progymnastic exercises of encomiastic topics and syncrisis in my monograph, The Characterization of Jesus in the Book of Hebrews. Moreover, Michael Martin and Jason Whitlark deal with syncrisis at length in structuring Hebrews' argument in Inventing Hebrews: Design and Purpose in Ancient Rhetoric. So, in fact, there has been more work done applying the progymnastic exercises of encomium and syncrisis to Hebrews than Neyrey gives credit for in his article. This is a surprising oversight from a scholar of the caliber of Neyrey.