The following is drawn largely from David Garland’s commentary on Mark.

Jesus’ entry into Jerusalem changes everything in His ministry. He has been moving about in secret, teaching in private, refusing to draw attention to Himself, speaking in coded parables. He cleanses a leper but then sternly warns him, “See that you say nothing to anyone” (1:44). He raises a little girl from the dead, but then “gave them strict orders that no one should know about this” (5:43). He heals deaf and mute man by touching and spitting, and then “gave them orders not to tell anyone” (7:35). He heals the blind man at Bethsaida, but then tells him to go home and not even enter the village where he was healed (8:26). Peter confesses that Jesus is the Christ, the Son of the Living God, but Jesus warns Him “to tell no one about it” (8:30), and after the transfiguration he “gave them orders not to relate to anyone what they had seen, until the Son of Man should rise from the dead” (9:9).

Jesus has been ministering mainly in Galilee and in the outskirts of the land. He has not visited Jerusalem. We have never seen Him in the temple in Mark’s gospel up to this point. Now, Jesus enters Jerusalem and the temple is the first place He goes, and the next several chapters take place in the temple, as Jesus duels with the Jewish leaders, until He goes to the Mount of Olives and declares that the temple is doomed.

Jesus has been walking everywhere. He has crossed the Sea of Galilee in boats a couple of times, but otherwise he has been on foot. We have not seen Him seated, enthroned, and we have not seen Him riding.

All this changes on Palm Sunday. Jesus is no longer keeping secrets. He is no longer avoiding public attention. He calls attention to Himself, by staging an entry. He accepts the acclaims of the crowd that He had earlier tried to suppress. He comes to Jerusalem, the center of Israel, and to the temple, the center of the center of Jerusalem. He comes to Jerusalem not walking but riding, acclaimed as a king, with the people singing and shouting and laying down the equivalent of a red carpet in His path.

Palm Sunday is an act of deliberate provocation, Jesus’ decision that the time has come to confront the Jewish leaders openly and on their turf.