What is the most abused passage in the Bible? Matthew 7:1? Leviticus 19:19? Probably both good candidates, but my vote is for 2 Peter 3 (especially verses 8-9). For one thing, the former two passages are usually abused by non-believers, whereas the last is usually abused by people who are (at least professing) Christians.
But more, 2 Peter 3 stands out as having been abused by so many different kinds of professing Christians! First, we have the old-earth creationists. There's evidence for and against old-earth creationism, and frankly I don't know which side of that debate I come down on. But surely 2 Peter 3:8 is not good support for any Christian? Its context has absolutely nothing to do with creation. As far as I know, until the mid-19th century nobody took this verse as support for an old earth. If it is support, then we'd have to admit a fatally flawed hermeneutical method, wrenching the verse out of context to make a point. This is called eisegesis, and I don't think we want to go there.
The second kind of Christian who have abused this passage is that group who recently had their day in the spotlight, followers of Harold Camping. Although their books provide many convincing (well, to "true believers" anyway) proofs of the October 21st end of the world, this verse is the foundation. Read for yourself in Camping's booklet "We are almost there". This understanding has a little better support than the first case of abuse (or frankly, than the third) since the passage is actually about judgment. But taking this as a mathematical formula, adding it to an assumed and arbitrary date of Noah's flood, and coming up with a date that conveniently falls with Camping's lifetime is a bit more than the text will bear, especially as the entire chapter of Matthew 24 militates against this as a possibility. (Note the tenor of the entire chapter fights it, not just 24:36, regardless of what Campingites would have us believe.)
But the third, and perhaps most egregious case of abuse against 2 Peter 3:8 is by traditional evangelical Christians. Everybody from Chuck Smith to Norm Geisler to Dave Hunt use this passage as one of their primary proof-texts against the doctrine of unconditional election. But surely this is a terrible case of eisegesis?
In my next note I will 'splain.