The following notes are from 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)
v. 15b: “. . . sacred writings that are able to instruct you
unto salvation through faith in Christ Jesus.”
v. 16a: “All scripture is life-giving [= salvific] and is
useful for instruction.” (p. 102)
Verse 16a effectively repeats the thought of v. 15b, but in an
abbreviated way, as the point of v. 16 is to expound on the several ways in
which this salvific is “useful” (ωφελιμος)—that
is, “for teaching, for reproof, for correction, and for training in
righteousness.” The idea of scripture being theopneustic is not the intruding
thought that the traditional rendering takes it to be but rather a restatement of
the previous verse’s point. As such, a vivificationist understanding of θεοπνευστος fits more snugly within the
passage than the traditional rendering does.
By viewing salvation in terms of life, the
understanding argued here invokes a soteriological conceptuality more
characteristic of the Pastoral Epistles than of any other portion of the New
Testament, except perhaps the Fourth Gospel Scholars often refer to salvation
as a key theme in the Pastorals, and they typically characterize that salvation
as the giving of life . . . This vivificationist soteriology comes to clearest
expression in 2 Tim. 1:10, where grace is said to have been “revealed through
the appearing of our Savior Christ Jesus, who abolished death and brought life
and immortality to light through the gospel” . . . 1 Tim. 1:16 speaks of those
who will gain “eternal life” (ζωην αιωνιον), and 4:10 similarly speaks of the “promise
of life” (επαγγελια ζωης). Tit. 3:7 speaks of the Spirit’s power to
make us heirs of “eternal life” (ζωης αιωνιου). (p. 103)