I've been going through a study in Jude and II Peter 2 for awhile now, taking it one phrase at a time and breaking down the meaning of each part of each verse, as it relates to the overall meaning of sections and the chapters as whole parts. Both chapters are very similar, written to churches warning them of "false teachers" and "ungodly men" that had crept into churches to try to do them harm, while acting like they were doing good. I thought I would begin to share these studies I've been going through.
Jude calls himself "the servant of Jesus Christ", instead of saying a brother of Jesus Christ. It would have been so easy to extort his position to gain fame or reward, but instead by this point has a better relationship with his brother and is doing the will of God (Mark 3:31-35).
The application: It is not anything that we have done, but what Christ has done through us. Therefore we must not use our position for pride or gain, but only to serve God.