I already written some things about the authorship of 2 Peter, so I’m not going to repeat all that here. Instead, I wish to reinforce a few of the points I’ve already made.
The primary objection to Petrine authorship has always been stylistic. Either considered on its own, or in relation to 1 Peter, it’s unlikely that the Apostle Peter could have written 2 Peter—or so goes the argument.
But there are at least a couple of basic problems with this line of objection:
1.Nigel Turner, who’s a leading authority on NT Greek, has documented a certain amount of “Jewish Greek,” in 2 Peter, consisting in Hebraisms and Septuagintalisms. Cf. N. Turner, A Grammar of New Testament Greek (T&T Clark 1980), 4:142-43. This would be quite consistent with Petrine authorship. It would be far less consistent for a 2C native Greek writer.
2.Ellis has also identified what he takes to be the extensive use of preexisting source material in 2 Peter:
“Cited traditions, interspersed with applicative commentary, form the substance of 2 Pet 1:20-3:13. They can often be identified by formulas used elsewhere to introduce quoted material,” E. E. Ellis, The Making of the New Testament Documents (Brill 2002), 120.
“The citations in 2 Peter noted above constitute c. 366 words out of a total of c. 1103=33% of the letter. They are part of two extensive commentaries, 2 Pet 1:20-2:22 and 2 Pet 3:3-13. If the two commentaries, i.e. midrashim are preformed pieces en bloc that the author has (reworked and) incorporated, as seems to be the case in Jude, the preformed material then constitutes c. 606 words or c. 55% of 2 Peter,” ibid. 122. (Cf. 132-33.)
If his analysis is essentially correct, then it makes it very difficult to isolate a Petrine style, for the style of the letter would largely derive from the secondary source rather than the primary source, i.e. the source material which Peter redacted for his own use.
It would also undercut the comparison with 1 Peter, for Ellis applies the same analysis to 1 Peter: “preformed traditions in 1 Peter constitute at least c. 652 out of a total of c. 1669 words, that is, 39% of the letter,” 138.
Needlessly to say, the traditional doctrine of inspiration has never precluded the use of preexisting material (e.g. the Chronicler).