There is a two-fold contrast of promises that Jesus makes to His disciples here. It is not particularly enjoyable to contemplate, but it is ultimately comforting. Jesus announces that He came into the world to bring peace to them through relationship with Him. That is well and good, but there is more to it. He could not guarantee that peace meant a conflict life in this world. It meant that pain would come from the world even while they were receiving peace in Jesus.
Christianity runs counterculture to the way things generally are in the world. We hold to absolute truth; the world runs from truth. We say sin brings judgment; the system says being bade is fun and a personal pleasure, even a right in some instances. We decry injustice and evil for what they are; the system perpetuates personal wealth and pleasure at expense of other people. All of that brings "tribulation" to those who swim against these currents.
Jesus' final words provide the perspective and encouragement we need: "...take heart; I have overcome the world." He would do so by dying on a cross at the hands of the powers of this world. He would then carry the sin of that world and later rise from the dead to offer victory over sin and death in this world to all who would change and be changed by trusting in Him.
- Posted with my iPad. The Apple Kool-Aide tastes fine.