Why did Jesus get so angry with Peter in today’s gospel (Matt 16:21-27)?

Let us look at this Gospel message from a different perspective.   Say  your father is at a very advanced stage of an incurable disease. He might not make it through the night, let alone a day or two.  As you  visit him, you wag your finger at him, and tell him that everyone is wrong about that terminal diagnosis; he surely will not die  so he'd better stop thinking about death. I know if it were my dad, he would ask me to get my head examined, and then tell me to shut up or leave him alone.

Now look at today’s Gospel story.  Jesus has just told the apostles that he would be murdered when they got to Jerusalem , but would be raised from the dead.  Picture the apostle Peter taking Jesus aside, wagging his finger in his face in a very scolding, reprimanding way [that is what the word “rebuke” means], and telling him that he has to stop talking such nonsense.  After all, it doesn't fit the “victorious warrior” image that befits the Messiah.  Jesus didn't lose a heartbeat.  He immediately told Peter to get out of his way; Peter was acting like a “Satan,” an obstacle in his path.

Peter just didn't “get it.”  To be Messiah did not mean to receive power and glory in the human political or military sense.  Rather, Jesus came to teach us that Messiahship means self-sacrifice and self-giving.  If that is true for the Messiah, then it is also true for his followers.  Peter, and you, and I have to rethink what it means to be a true disciple.  There is no room for seeking honor and glory; there is only room for self-sacrificing love.  Your home and your workplace are the testing grounds to prove your ability to use these weapons effectively.

Peter’s scorn for Jesus’ prediction (CCC #554) would soon change to recognition of the need to “deny self” and follow Jesus, even with our crosses (CCC #2029).  This actually makes us “partners” in this redemptive mystery (CCC #618).