Thomas Aquinas Commentary John 13:36-38

"Simon Peter saith unto him, Lord, whither goest thou? Jesus answered, Whither I go, thou canst not follow now; but thou shalt follow afterwards. Peter saith unto him, Lord, why cannot I follow thee even now? I will lay down my life for thee. Jesus answereth, Wilt thou lay down thy life for me? Verily, verily, I say unto thee, The cock shall not crow, till thou hast denied me thrice." — John 13:36-38 (ASV)

1. Above, John mentioned the defection of one of the disciples, Judas the traitor; here he tells of the failure of another, Peter, who denied Christ.

   First, we see the occasion of Christ’s prediction; second, the prediction of Peter’s denial: Jesus answered him, "Will you lay down your life for me?"

   Regarding the first point, the occasion, the author considers two things: first, Peter’s desire, and second, his confidence: Peter said to him, "Why can I not follow you now?"

   Regarding Peter's desire, the author shows two things: first, Peter expressing his desire, and second, that its fulfillment will be delayed: Jesus answered, "Where I go, you cannot follow me now."

2. Peter’s desire is shown by the quick way he questioned Christ: Simon Peter said to him, "Lord, where are you going?" Peter had heard our Lord say that he would be with them for just a little while, and he became anxious about Christ’s leaving them. So he asks, "Where are you going?"

   Chrysostom says about this: Peter’s love was indeed great, and more furious than a fire that nothing could stop. This is why even after Christ had said, "Where I am going, you cannot follow," Peter still wanted to follow him. So he asked where he was going, just as we read: "Where has your beloved gone, O fairest among women? Where has your beloved turned, that we may seek him with you?" .

3. Yet Peter cannot have what he desires now, since for the present he is prevented from following Christ: "Where I am going, you cannot follow me now; but you will follow hereafter." This is like saying, "You are still imperfect, and thus not able to follow me now; but later, when you are perfect, you will follow me." This is similar to what we will read further on: "Truly, truly, I say to you, when you were younger, you used to gird yourself... but when you are old, you will stretch out your hands, and another will gird you" (John 21:18).

4. When John says, Peter said to him, he indicates Peter’s confidence. Peter had understood what our Lord had just said as expressing some doubt about the perfection of his love. Love is perfect when one exposes oneself to death for a friend: "Greater love has no one than this, that someone lay down his life for his friends" (John 15:13). And so because Peter was ready to die for Christ, he declared that he was perfect in love when he said, "I will lay down my life for you," meaning, "I am ready to die for you." He really meant this and was not pretending. Still, we do not know the strength of our own love until it meets an obstacle to be overcome: "I am not aware of anything against myself, but I am not thereby acquitted" (1 Corinthians 4:4).

5. Next, John shows Jesus predicting Peter's denial: Jesus answered him, "Will you lay down your life for me?"

   In this, Jesus does two things:

   • First, he checks Peter’s presumption.
   • Second, he predicts his denial: "Truly, truly, I say to you, the rooster will not crow until you have denied me three times."

6. As to the first point, we should note that after Christ said, "You cannot follow me now," Peter was confident in his own strength and said that he could follow Christ and die for him. Our Lord checked him by saying, "Will you lay down your life for me?" It is as if to say, "Think about what you are saying. I know you better than you know yourself; you do not know how strong your own love is. So do not assume that you can do everything." As it is written: "So do not become proud, but stand in awe" (Romans 11:20). A similar thought is found in Matthew: "The spirit indeed is willing, but the flesh is weak" (Matthew 26:41).

   Our Lord allowed Peter to be tempted and to fall so that when he became head of the Church, he would have a humble opinion of himself and have compassion for his subjects when they sinned: "For we do not have a high priest who is unable to sympathize with our weaknesses, but one who in every respect has been tempted as we are, yet without sin" (Hebrews 4:15). In Peter, some temptations grew into sins. But Christ was tempted as we are, not because he committed sin, but because the temptations were penal in character.

7. Christ predicts Peter’s denial when he says, "Truly, truly, I say to you, the rooster will not crow until you have denied me three times."

   This phrase, "the rooster will not crow until you have denied me three times," causes a problem, as it seems to be false; for in Mark we read that the rooster crowed immediately after his first denial (Mark 14:68).

   Augustine answers this in two ways.

   1. First, he says that our Lord was expressing Peter’s state of mind rather than his actions. Such fear had overcome Peter’s soul that he was ready, by the time the rooster crowed, to deny our Lord not only once but three times. So the meaning is: you will be ready to deny me three times before the rooster crows.
   2. Second, he explains it another way by saying the prediction refers to the very beginning of Peter’s denial. Something is said to happen before something else even if it only begins to happen. Our Lord predicted three denials, and they began before the first rooster-crow, although the entire series was not completed before it. Here the meaning of "Truly, truly, I say to you, the rooster will not crow until you have denied me three times" is: your triple denial will begin before the rooster crows.

8. There is also a question about where these words were spoken. Matthew and Mark say that our Lord said this to Peter after they had left the upper room, but Luke and John say he said this in the upper room. It is after the farewell discourses that John has Jesus saying, "Arise, let us go from here" (John 14:31).

   In answer to this, we should say that it is true that our Lord said this in the upper room. Matthew and Mark did not follow the order of history, but of memory.

   One could also say, with Augustine, that our Lord said this three times. A close inspection of our Lord’s words which led to his predicting the denial of Peter shows that three different things were said. In Matthew we read that our Lord said, "You will all fall away because of me this night" (Matthew 26:31), and Mark says the same (Mark 14:27). Peter answered, "Though they all fall away because of you, I will never fall away" (Matthew 26:33). Then Jesus said, "This very night, before the rooster crows, you will deny me three times" (Matthew 26:34). In Luke, however, we read that Jesus said, "Satan demanded to have you, that he might sift you like wheat, but I have prayed for you that your faith may not fail" (Luke 22:31). Peter then said, "Lord, I am ready to go with you to prison and to death" (Luke 22:33). Our Lord answered this: "I tell you, Peter, the rooster will not crow this day, until you three times deny that you know me" (Luke 22:34). But here, in John, when Peter asked our Lord where he was going, our Lord replied, "The rooster will not crow until you have denied me three times." We can conclude from this that our Lord predicted Peter’s denial several times.