Today's readings pretty much sum up the paradox that we call the "good news." In the Gospel, Jesus is saying (among other things), "the Son of Man [Jesus himself] ... will be condemned to death, handed over, mocked, spit on, scourged and killed." And "whoever wishes to be great among you will be your servant...and the slave of all."
It's not only in the Gospel of Mark that we find this sort of language: John saves it for the Last Supper, when Jesus acts the part of a slave, washing the disciples' feet while explicitly emphasizing that he is doing this as their "Master and Lord." And St. Paul, too, consistently referred to himself with terms like "servant" and "slave."
I strongly suspect that the disciples (whether of Jesus, John or Paul) did not especially like where all this talk was going. It's the opposite of our expectations--as today's Gospel also makes clear: "Rulers among the Gentiles lord it over them and make their position felt." That's exactly what James and John were looking for when they asked for places at Jesus' right and left in the kingdom. They got what they were asking, even though they didn't know what they were really asking for.
All that Jesus was doing was to undo the primordial sin and every sin since then, all originating in the will to a misbegotten form of greatness.