chiasm: Hebrews 3.1-12.29

What would you say is the centerpiece, the primary point of emphasis, of the letter/sermon we know today as Hebrews?

It might be helpful to know that the vast majority of the material of Hebrews can be viewed as a single, large chiastic structure.

Chiasm-Hebrews-3-12

Credit: Morna Hooker, cited in New Testament Rhetoric by Ben Witherington (Cascade, 2009); p.201