Despite his pledge to die for Jesus if necessary, in his weakness Peter denied that he knew Jesus.
John 13:31-38
As soon as Judas left the room, Jesus said, “The time has come for the Son of Man to enter into his glory, and God will be glorified because of him. And since God receives glory because of the Son, he will give his own glory to the Son, and he will do so at once. Dear children, I will be with you only a little longer. And as I told the Jewish leaders, you will search for me, but you can’t come where I am going. So now I am giving you a new commandment: Love each other. Just as I have loved you, you should love each other. Your love for one another will prove to the world that you are my disciples.”
Simon Peter asked, “Lord, where are you going?”
And Jesus replied, “You can’t go with me now, but you will follow me later.”
“But why can’t I come now, Lord?” he asked. “I’m ready to die for you.”
Jesus answered, “Die for me? I tell you the truth, Peter—before the rooster crows tomorrow morning, you will deny three times that you even know me.
John 18:15-18, 25-27
Simon Peter followed Jesus, as did another of the disciples. That other disciple was acquainted with the high priest, so he was allowed to enter the high priest’s courtyard with Jesus. Peter had to stay outside the gate. Then the disciple who knew the high priest spoke to the woman watching at the gate, and she let Peter in. The woman asked Peter, “You’re not one of that man’s disciples, are you?”
“No,” he said, “I am not.”
Because it was cold, the household servants and the guards had made a charcoal fire. They stood around it, warming themselves, and Peter stood with them, warming himself.
Meanwhile, as Simon Peter was standing by the fire warming himself, they asked him again, “You’re not one of his disciples, are you?”
He denied it, saying, “No, I am not.”
But one of the household slaves of the high priest, a relative of the man whose ear Peter had cut off, asked, “Didn’t I see you out there in the olive grove with Jesus?” Again Peter denied it. And immediately a rooster crowed.