There is something that happens in a Christian that is considered blindness; something that is considered to be extreme memory loss. This "something", if NOT done, will keep you from confirming your "call and election". It is so important the Peter says to "be diligent" in this area so you do not fall. Some Bible translations say, use the word "stumble".
I am not entirely sure what the meaning of this word is in the original, but a little research returned the result of, "come to ruin". In James 2:2 the same word is used and is translated "fail". Whatever is most accurate, it is clear that "falling", "stumbling", "failing", or "coming to ruin" are not good. At the least it will make you unfruitful, and at the most it might prove to find that your faith is not genuine.
What is this "something"? The "something" is qualities that you must not only have, but they must be increasing. Many times in Scripture we see very stark contrasts, for example, one is either heading for glory unspeakable, or they are heading for condemnation unimaginable. I am not entirely sure, but 2Peter 11 seems to be one of those, although