I am actually friends with a good number of successful professional Christian musicians, including members of Dizmas and Adam's Housecat. Mr. Of-Gold is absolutely right. Almost every truly Christian band that makes it does so as part-ministry, part-band. Even the big names, like the Newsboys, Third Day, etc, follow this philosophy. There are lots of band prayers, band devotionals, etc. Many, even the metal bands, also do praise and worship together at churches, both to learn that style, and to be playing together more and getting tighter. I have actually performed in Christian bands, and the number one rule always seems to be "ministry before music." A lot of the places that you play, people will see you on stage and, whether fair or not, will think of you as spiritual leaders. Thus, having non-Christians in your Christian band becomes a real issue. If a person at a show goes up to the guitarist and asks a spiritual question, and gets, "How the hell should I know?" or "I don't buy this stuff," it becomes an issue. A band can be destroyed by a member sleeping with a member of the audience, etc.