2:1–10a · Certainty of judgment: At this point our author reveals his central concern, as he incorporates the material he takes from Jude. There were false prophets in the past, and there are false teachers now. In Jude the others are outsiders, never named, and never said to be teachers. Here they are insiders (“among you”) who are “false teachers,” and it is only the new ideas that come from outside. (They “introduce” them.) The phrase “destructive heresies” means not so much false doctrine (the denial of the return of Jesus is a secondary issue and so left to last) as ideas that lead to divisions in the community. (“Heresy” indicates they separated into a party or sect.) It is also clear that these ideas lead to “depraved conduct” (some form of promiscuity) that even those in the larger…