Specifically, the nine notes the choir used to sing the line "thou shalt rest, thou shalt rest" have been stuck in my head (where they've had plenty of room to bounce around) for decades. And since I've been getting frisky with a music writing software I bought first to write plain lead sheets, Finale PrintMusic, digging into it deeper and---remembering what I learned of music notation from a year of boyhood piano lessons (sorry, piano lovers, but I gave it up for a guitar!)---getting brazen enough to write full scores with plenty of improvisational room.
This song, "Rest," was written originally for my own blues group in the making, a lineup of tenor sax, keyboard, bass, drums, and yours truly on guitar. Taking frisky to an extreme, I wrote this score for an octet of flute, trumpet, tenor sax, trombone, guitar, bass, and drums.
The kicker: The Finale program will also play back what you write and turn it into a sound file. With that conversion leaving the silences where I marked for improvisation (the program treats the slash notation you use to indicate improvisational passages in jazz and blues writing), I winged demo flute and trumpet solos off my electronic keyboard, then plugged in my Les Paul, running the neck pickup alone, and winged a demo guitar solo.
Here it is . . .
Rest.