When I’m at Mass, I often find myself at the edge of sleep and occasionally right over it into a twenty-second burst of shallow, eye-closing, neck-relaxing sleep. This can happen during the Gloria, or the Creed, or even the Sanctus, short though it is; sometimes, though much less often, it happens during the homily or the readings; and perhaps most often it happens during the Eucharistic prayer, where I can drowse in an incense-threaded, bell-punctuated haze. And even when I don’t actually sleep, I often spend some part of the liturgy in lullaby-lulled somnolence. I think of this as the liturgical drowse.
The liturgical drowse doesn’t, I think, prevent me from speaking my part (though I may not be the most reliable witness). I can easily recite the Creed in my sleep—perhaps more easily than when fully awake and thinking about it. And the same goes for the other parts of the Mass written on my memory. But the drowse does prevent me from being aware that I’m saying my part as I say it; and sometimes it’s deep enough that even when I rerun things in my mind—as you do when you’ve heard a clock strike without counting and then do a mental replay to figure out what hour it is—I can’t be sure whether I continued to vocalize. I become, when enjoying the deeper forms of the liturgical drowse, something close to an automaton, though one perfectly capable of fairly complex action and utterance.