John Chrysostom — as excerpted in the Catena Aurea on Matthew 26:30-35

“What sayest thou, Peter? The Prophet says, The sheep shall be scattered abroad, and Christ has confirmed it, yet thou sayest, Never. When He said, One of you shall betray me, thou fearedst for thyself, although thou wert not conscious of such a thought; now when He openly affirms, All ye shall be offended, you deny it. But because when he was relieved of the anxiety he had concerning the betrayal, he grew confident concerning the rest, he therefore says thus, I will never be offended.”