The problem with taking 2 Pet. 1:21 as a
support for the inspiration of Scripture should be obvious for anyone who reads
it slowly and deliberately: It does not refer to the inspiration of Scripture
per se but rather to the inspiration of prophecies within Scripture (v.
20). Nothing in the verse implies that epistolary and narrative writings found
within Scripture are also inspired. The discussion leading up to 2 Pet. 1:21
has to do with the assuredness of the Lord’s word, as delivered in a prophetic
mode. Nothing in this verse can reasonably be construed as a statement about
the nature of Scripture itself. (John C. Poirier, The Invention of the Inspired
Text: Philological Windows on the Theopneustia of Scripture [Library of New
Testament Studies 640; London: T&T Clark, 2021], 110, emphasis in original)
