But false prophets also arose among the people, just as there will be false teachers among you, who will secretly bring in destructive heresies, even denying the Master who bought them, bringing upon themselves swift destruction. And many will follow their sensuality, and because of them the way of truth will be blasphemed. And in their greed they will exploit you with false words. Their condemnation from long ago is not idle, and their destruction is not asleep.
2 Peter 2:1-3
The warnings against false teachers follow naturally after what Peter has said about the true prophets of God. Wherever and whenever God has spoken, Satan has tried to counteract the living truth with his lies. This is a greater danger today than some seem to think. False sects abound in our time and their persistent door-to-door visitation makes it advisable for us to be on our guard against them. Many of them share common ground in denying the Deity and Godhead of Christ, thereby undermining and destroying the only true basis for atonement, and leading to views of salvation that are often the antithesis of the clear-cut and unambiguous testimony of the early Church that there is 'none other Name under heaven given among men whereby we must be saved' save the Name of Jesus'.
Peter has already given us an indication of how to recognise, and deal with, false teachers. We may apply their teaching to the touchstone of scriptural teaching concerning Christ in His Person and Work. But more. He asserts here (2) that there is a connection between false doctrine and wrong living ('pernicious' should read 'lascivious'). When a man strays from the truth of God, it is very often not an intellectual or doctrinal problem, but a moral one, that lies behind his declension. The word 'heretic' primarily means one who causes divisions, and the root idea is that he 'chooses on his own' to depart from the truth and propagate different teaching. Hence heresy comes to mean false teaching. The important thing to remember is that heresy begins with a moral problem, self-will, self-assertion, self-display, and it is this that Peter has in mind here.