Peter's denial of his impending denial in Matthew 26 is a reminder to every follower of Jesus that over-confidence is the first step toward falling. The more confident we are in our own dedication, devotion, and ability to withstand temptation the further down we have let our guard.
We are like a fighter who gets so confident in our ability, we start to let down our guard to a point when our formidable foe takes the chance we gave him in our over-confidence to knock us out.
When Jesus tells his disciples [us] that we will fall away, it ought to be a sobering reminder to take this seriously and realize we are not as strong as we think we are. We ought to humbly keep our guard up.