16 He writes the same way in all his letters, speaking in them of these matters. His letters contain some things that are hard to understand, which ignorant and unstable people distort, as they do the other Scriptures, to their own destruction.

Read 2 Peter 3:16 Using Other Translations

As also in all his epistles, speaking in them of these things; in which are some things hard to be understood, which they that are unlearned and unstable wrest, as they do also the other scriptures, unto their own destruction.
as he does in all his letters when he speaks in them of these matters. There are some things in them that are hard to understand, which the ignorant and unstable twist to their own destruction, as they do the other Scriptures.
speaking of these things in all of his letters. Some of his comments are hard to understand, and those who are ignorant and unstable have twisted his letters to mean something quite different, just as they do with other parts of Scripture. And this will result in their destruction.