From: Mark 9:30-37
Second Prophecy of the Passion
 They went on from there and passed through Galilee. And He (Jesus) would not have any one know it;  for He was teaching His disciples, saying to them, "The Son of Man will be delivered into the hands of men, and they will kill Him; and when He is killed, after three days He will rise."  But they did not understand the saying, and they were afraid to ask Him.
Being the Servant of All
 And they came to Capernaum; and when He was in the house He asked them, "What were you discussing on the way?"  But they were silent; for on the way they had discussed with one another who was the greatest.  And He sat down and called the Twelve; and He said to them, "If any one would be first, he must be last of all and servant of all."  And He took a child, and put him in the midst of them; and taking him in His arms, He said to them,  "Whoever receives one such child in My name receives Me; and whoever receives Me, receives not Me but Him who sent Me".
30-32. Although moved when He sees the crowds like sheep without a shepherd (Matthew 9:36), Jesus leaves them, to devote time to careful instruction of the Apostles. He retires with them to out-of-the-way places, and there He explains points of His public preaching which they had not understood (Matthew 13:36). Here, specifically, for a second time, He announces His death and resurrection.
In His relationships with souls Jesus acts in the same way: He calls man to be with him in the quiet of prayer and there He teaches him about His more intimate plans and about the more demanding side of the Christian life. Later, like the Apostles, Christians were to spread this teaching to the ends of the earth.
34-35. Jesus uses this argument going on behind his back to teach His disciples about how authority should be exercised in His Church--not by lording it over other, but by serving them. In fulfilling His own mission to found the Church whose head and supreme lawgiver He is, He came to serve and not to be served (Matthew 20:28).
Anyone who does not strive to have this attitude of self-forgetful service, not only lacks one of the main pre-requisites for proper exercise of authority but also runs the risk of being motivated by ambition or pride. "To be in charge of an apostolic undertaking demands readiness to suffer everything, from everybody, with infinite charity" ([St] J. Escriva, "The Way", 951).
36-37. To demonstrate to His Apostles the abnegation and humility needed in their ministry, He takes a child into His arms and explains the meaning of this gesture: if we receive for Christ's sake those who have little importance in the world's eyes, it is as if we are embracing Christ Himself and the Father who sent Him. This little child whom Jesus embraces represents every child in the world, and everyone who is needy, helpless, poor or sick--people who are not naturally attractive.
Source: "The Navarre Bible: Text and Commentaries". Biblical text taken from the Revised Standard Version and New Vulgate. Commentaries made by members of the Faculty of Theology of the University of Navarre, Spain. Published by Four Courts Press, Kill Lane, Blackrock, Co. Dublin, Ireland. Reprinted with permission from Four Courts Press and Scepter Publishers, the U.S. publisher.