John has a message from Jesus to the church of Laodicea that they are "lukewarm" – neither hot nor cold. The temptation is to think that Jesus was telling the church not to be "lukewarm Christians", but the problem is that the context doesn't support that idea. To really understand what Jesus meant you have to first understand the cultural context of Laodicea and its water source. The nearby town named Hierapolis that was well known for it's glorious hot springs, and Colosse was also close by with a wonderful cool spring running through it that provided refreshing, safe drinking water. Laodicea, on the other hand, had stale, stagnant water that the people hated. Jesus essentially said, "I think about you the way you think about your water: it's useless, and you want to spit it out of your mouth!" It wasn't good for bathing or for drinking; it had no value. Jesus' desire for them was that they would be useful for something rather than nothing. The hot water was good for bathing, and the cold water was good for drinking; the lukewarm water was good for nothing. So the bigger question is: what are you good for? Are you benefiting your local church? Are you growing in your relationship with the Lord? Are you spreading the Gospel to those around you? Those are the marks of a useful Christian.