I ask this because I sing in a church choir, and sometimes play the organ. I really love doing both, but I do find that it often means I'm not concentrating on the service at all; instead I'll be thinking about the awkward line of harmony in the next hymn. (I am relatively new to being in a choir; I'd never sung harmony before I joined.)
I have noticed that if I attend a service when I am not performing, especially if at another church, I do concentrate a lot more on what is being said.
I have also told myself that if I do really want to appreciate the service and its spirituality, perhaps following a bereavement, I might choose to sit out the choir for a few weeks.
Is it normal to feel this way? Do more experienced choristers and organists still have to devote their concentration to their music, rather than the service?