Meaning by Extension, Cont'd
The "rest stop" on the highway. Euphemistically, a "restroom." Your personal trainer might suggest that you take a rest between reps. Even God Himself, on the Seventh Day, rested.
All implying a time-limited respite, after which the animated subject will be back in action.
But inanimate things can rest as well. A body at rest tends to remain at rest. That polished stone has rested on my mantle since I placed it there, in 1973. The waitress is nervous because the crystal glass rests half on, half off the table.
And so we use this duality to play a trick when referring to the dead. The minister intones that Claudia is not really dead. Today we take her to her eternal rest, which, eternal or not, implies getting back up again when circumstances permit. Indeed, according to the Apostles Creed, He will come to judge the living and the dead on the Last Day, when all shall be raised.
And of course, even if we don't believe, we still wish that all but the most dastardly may ... rest in peace.