When having band rehearsal for a church service, one of the basic things that one must get right is the difference between a “practice” and a “rehearsal”.
In a nutshell, practice means perfecting a technique, whether it be playing an instrument or singing a melody, on your own. Practicing something really focuses on perfection – you’re trying to execute something flawlessly. That’s why you typically practice on your own – so you can repeat things ad infinitum without annoying anyone!
Rehearsals are group events where everyone (having practiced their individual tasks/parts) puts everything together to make a set. In our church rehearsals are often the place where we make changes to the order of songs, but we don’t normally change which songs are done. Most people have been practicing those songs at home before the rehearsal – so you can’t go changing songs at the rehearsal.
Saying practice sessions are limited to a single person is not always the case. Sections of the band can arrange to do practice sessions – for example the drummer and bassist (maybe also electric guitar) can meet up somewhere for an hour to practice and nail some tricky bits. Vocals and the piano player can do the same. When they subsequently show up at rehearsal the songs in question will just flow.
Of course a system like MindMyMinistry makes practicing and rehearsals much easier, because songs are available for everyone to see weeks before the actual service. Rehearsals are also scheduled right on each event (service), so everyone knows when and where they are expected to attend.
Long story short – don’t practice at rehearsal. Rehearsals are meant to glue everything together – nothing more.