From that time Jesus began to show his disciples that he must go to Jerusalem and suffer many things … Matthew 16:21
We have come to a new section of Matthew’s Gospel where Jesus begins to reveal His mission and work. Having understood the nature of the Person of Jesus as the Christ, the Son of the living God, the disciples will now be confronted with a different idea of the mission of Christ, than they were familiar with. While they acknowledged Jesus’ messiahship, they would now begin to learn that this Messiah’s work involved suffering and death, and to follow Him would likely mean their own death as well.
In this text we have the very first definite prediction of Jesus’ passion (which will be repeated in 17:22-23, and 20:18-19). The Jewish people’s idea of the Messiah, for the most part, was that he would triumphantly reign over the world from Jerusalem. The idea that the Messiah would go to Jerusalem to suffer, was beyond their ability to comprehend, so much so that Peter actually rebuked Jesus for having been mistaken in suggesting such a shocking thing. Even though Peter just confessed Jesus to be the Son of God, he had much to learn about what it meant to follow Him. Jesus revealed that Peter’s rebuke was the result of setting his mind on the things of self, rather than the things of God.
Jesus took this first revelation of His own suffering as an opportunity to teach the disciples about living a life of self-denial and even death to self; in verse 24 He said, “If anyone would come after me, let him deny himself and take up his cross and follow me.” For a disciple, to follow his teacher meant that he would live and die as his Rabbi did. So as Jesus did not live for himself, the call to discipleship involves repudiating every link that ties us to ourselves–in the words of one commentator, “obliterating self as the dominant principle of life in order to make God that principle.” To “take up one’s cross” unquestionably pointed to the humiliating practice of a condemned criminal carrying the very instrument of his own execution, through the streets, bearing the shame of onlookers, ultimately to his death. Ironically Jesus tells us that this is the only way to find true life. If our own physical well-being is the dominant principle of life, we will end up losing our lives. Practically speaking, this means that self-interest ends up killing us, while living for God and others results in real life.