(34) I tell thee, Peter.--See Notes on Matthew 26:34-35; Mark 14:30-31,

22:21-38 How unbecoming is the worldly ambition of being the greatest, to the character of a follower of Jesus, who took upon him the form of a servant, and humbled himself to the death of the cross! In the way to eternal happiness, we must expect to be assaulted and sifted by Satan. If he cannot destroy, he will try to disgrace or distress us. Nothing more certainly forebodes a fall, in a professed follower of Christ, than self-confidence, with disregard to warnings, and contempt of danger. Unless we watch and pray always, we may be drawn in the course of the day into those sins which we were in the morning most resolved against. If believers were left to themselves, they would fall; but they are kept by the power of God, and the prayer of Christ. Our Lord gave notice of a very great change of circumstances now approaching. The disciples must not expect that their friends would be kind to them as they had been. Therefore, he that has a purse, let him take it, for he may need it. They must now expect that their enemies would be more fierce than they had been, and they would need weapons. At the time the apostles understood Christ to mean real weapons, but he spake only of the weapons of the spiritual warfare. The sword of the Spirit is the sword with which the disciples of Christ must furnish themselves.And he said,.... "To him", as all the Oriental versions add; to Peter, as what is said shows; that is, Jesus said to him, as the Syriac and Persic versions express:

I tell thee, Peter; who knew him, and his heart, better than he did himself, as well as knew what was to come, and what would befall him; and therefore declares it, as he does with the greatest assurance and certainty, and which might be depended on, and accordingly came to pass:

the cock shall not crow this day; in this night, as in Mark 14:30 or this night, as in Matthew 26:34 for it was now night; a natural day includes both night and day; a like way of speaking, see in Luke 2:8

before that thou shalt thrice deny that thou knowest me; as he did, Luke 22:57. See Gill on Matthew 26:34.