For biblical authority, 2 Timothy 3:16 is generally the quintessential statement. As a result, inspiration is commonly understood to be the act of God breathing words as authors wrote.
But that neglects the rest of the canon. The overwhelming evidence demonstrates that divine truth was revealed primarily by God speaking. Though there is still an element of mystery, revelation was more audible than inaudible.
This paper reviews the nature of inspiration genre by genre throughout Scripture. While the word “inspired” can be rightly used for the authority of written Scripture, “inspiration” is no less applicable to the oral words of God. As stated by Peter Williams in the edited book, The Enduring Authority of the Christian Scriptures, “There is no sense in which God’s words become more inspired by virtue of being written down.”
In addition to God himself speaking with authority, he passed his role on to viceregents, whom he prepared, authorized, and empowered to speak on his behalf. Their spoken words were no less authoritative and inspired than those of God himself.
Regarding 2 Timothy 3:16, most interpreters questionably use the etymology of the term theopnuestos to determine its meaning. But as summarized, for example, in 2 Peter 1:20-21, the authorized and Spirit-directed spokespersons of Scripture provide the basis for the authority of the written revelation. The inspiration of written Scripture is derivative, therefore, not independent.
While the book entitled, The Voice of God in the Text of Scripture—consisting of papers from the Los Angeles Theology Conference (2016)—might seem to make the paper I’m proposing unnecessary, I’ve been unable to find any source that carefully considers the scope of evidence for a biblical theology of authority.