What does Matthew 26:33 mean?

Peter, as pictured in the Gospels, is ever brash and often wrong. That fearlessness, though, makes him a natural leader for the rest of the disciples. He often boldly says what they are all feeling. Earlier, Peter heard Jesus predict that one of the group would become a traitor (Matthew 26:21). He's taken in the more recent prediction that all the disciples would "fall away" that very night (Matthew 26:31). Jesus has not condemned them, rather promising they will be reunited after He is resurrected (Matthew 26:32). Peter, though, hears only the prediction of failure and disloyalty and cowardice on their part. He refuses to believe it.

This leads to a heartfelt, but foolish declaration from Peter: even if everyone else fails you, I never will! That probably sounded insulting to the other disciples. And yet, Jesus knows Peter's confidence in his own strength will not be enough in the coming hours (Matthew 26:56; 69–75). Peter will learn, eventually, that Jesus does not want followers who are strong in themselves but who rely on Him.