Matthew Henry on Matthew 26:31-35

Improper self-confidence, like that of Peter, is the first step to a fall. There is a proneness in all of us to be over-confident. But those fall soonest and foulest, who are the most confident in themselves. Those are least safe, who think themselves most secure. Satan is active to lead such astray; they are most off their guard: God leaves them to themselves, to humble them.