This Gospel passage has for quite awhile now been recognized by scholars as a key, pivotal moment of the entire Marcan Gospel. The first 8 chapters have given all the indications to justify the estimates: you are a prophet, you are Elijah, you are John the Baptist...and the Petrine estimate: you are Messiah. But within a few lines Jesus has practically denied being Messiah, the one who will provide us with all the blessings of God's kingdom. He says he will die a terrrible death, such a death as will contradict his power, his wisdom, his union with God. Such a gruesome end to Jesus makes absolutely no sense, Peter says: it is impossible.
What is the link between power and powerlessness, innocence and guilt, wisdom and foolishness? The contradiction between the first 8 chapters of the Gospel and the remaining chapters filled with prediction of death and moments of conflict and a minimal number of miracles and the absence of admiring crowds - all of these contradictions end when one repeats what Jesus said at the beginning of his public life. In temptation, Jesus responded that he lived by God's word, that he was lived with Yahweh as his God, that he lived in absolute trust in God's love for him, no matter what might happen to him. What unifies the life of Jesus, then, and makes total sense of his life is his filial obedience to his Father. He knew he was called to ask people to repent and he realized that his Father wanted him to die. His reaction to both requests was filial obedience. If you prefer to think not of obedience, but rather of what spurred him to obey, you can say the unifying thread through the most contradictory elements of his life was his love of his Father. If the Father asked him for x, he did x; and if his Father asked for y, Jesus did y. There may appear to be reversal in the fate of Jesus, but that is only appearance. What is the truth is that, from beginning to end, whether all-powerful or crucified, obedience remains the same, love remains the same.
Peter did not see that crucifixion would be another moment in Jesus' acts of obedient love; thus, he could not accept it, not for Jesus, not for himself. Yet, Jesus knew what life should be: the living and loving obedience, which from Adam downward characterizes human relations with God. If there is a Messianic secret about Jesus' life, i.e. a silence for a long time on his part about his future, the truest secret, the truest reality is Jesus' readiness to do what his loving Father asked him to do.
Such was the major lesson of Mark to his readers in Rome, and such is Jesus' major lesson to us today.
John Kilgallen, S.J.