I don't play guitar, but from working with them over the years, I've picked up a few things, one of which is that they hate playing an F major chord. A lot of sacred music is in "flat keys" (F, Bb, Eb, etc) which I understand is a pain for guitarists. You don't like F? Fine, put a capo on the first fret and play it in E. Ta-da! You don't like Eb? Capo 1 and play it in D. Ta-da! It blows me away when I have to point that out to them.
One time during rehearsal, one of my guitarists Dan was trying to play some chord and the other one Dusty was showing him. "Okay, it's just like this... good... now raise your middle finger..." and Dan looks at him and goes "Yeah, I'll raise my middle finger" and we're (jokingly) like "Whoa, guys, we're in church here!"
Then it became a thing. I was leading rehearsals at that point, and we were trying to get a certain part right and it was all "How about I just raise my middle finger?" Kinda funny for a while, but thankfully didn't last long.