Pope Peter’s penmanship presents a problem for Presbyterians’ perspective on perseverance.
I am sure I will suffer for that alliteration someday, but it was worth it.
[A]nyone who has escaped the pollution of the world by coming to know our Lord and Saviour Jesus Christ, and who then allows himself to be entangled and mastered by it a second time, ends up by being worse than he was before. It would have been better for them never to have learnt the way of uprightness, than to learn it and then desert the holy commandment that was entrusted to them. What they have done is exactly as the proverb rightly says: The dog goes back to its vomit and: As soon as the sow has been washed, it wallows in the mud. (2 Pt. 2:20-22, NJB; emphasis added)
St. Peter makes it pretty clear: there are people who come to know Christ the Savior who then stumble and fall, becoming worse sinners than they were before. But if Presbyterian views of the perseverance of the saints were correct, this should be impossible: no non-elect person can be said to “come to know Christ,” and we are told that the elect will not fall away for good. But nothing in the passage above suggests that these people come back. So it appears that this passage from 2 Peter undermines the Presbyterian/Reformed idea of the perseverance of the saints. Instead, we see hear a warning: don’t fall away! Such a warning is pointless for both the Elect and the Reprobate in the Reformed scheme: the Elect won’t fall away, the Reprobate were never anything but fallen anyway. Peter’s warning makes no sense in such a scheme.