I really enjoyed my church's Bible study group last night. Actually, going through Margaret Feinberg's Scouting the Divine: Searching for God in Wine, Wool, and Wild Honey has been a rewarding experience overall, for the people in the group have opened up about such issues as service, how they pray, how they study the Bible, etc.
I especially liked a story my pastor told about how he worked at a retirement home and became friends with one of the residents there, and my pastor was sad when that resident died. Speaking personally, I think that service can be a rewarding experience for me, if it's confined to me visiting and socializing with people who are lonely, such as the elderly or the sick. I can also tutor people one-on-one, which I've been good at in the past. But when service becomes a job in which intense demands are placed on me and I'm evaluated, or I'm given a bunch of tasks that I have difficulty handling, then service is not rewarding, anymore.