Hubby and I visited a church for the first time this morning and witnessed something -- a small thing, I admit -- that we didn't think looked right.
The minister and his liturgical assistants -- four in total -- drank water out of bottles, including one who drank water out of a bicyclist's squeeze bottle. This looks bad. There's no way to effectively drink from a bottle without bunching up your face into a pucker, which you might not notice on the street or office but is unavoidable when you're in the pew and looking towards "the action." It's facial gesture you associate with a suckling babe or an unpleasant or tart taste. Because one normally doesn't up-end a bottle in the pulpit, the drinking gesture is more akin to a nip from a hip flask. You don't associate it with control, serenity or good production values.
A glass is better, and clear glass is less conspicuous. A bedside glass with matching pitcher or carafe seems like a good option. Or perhaps a travel mug without a handle, if tipping is a concern. I wouldn't blanch at a clear wide-mouthed Nalgene bottle, if the congregation was reasonably sporty (or else if might look like you're drinking from a canning jar, which itself might be appropriate in Muncie, Indiana, birthplace of the Ball jar.) [Later. See the comments for a cautionary tale about the Nalgene bottle.]
Oh, and don't duck behind the pulpit and try to drink upside down. You're not trying to cure hiccups. It takes longer and is more distracting than pulling the glass up to your mouth and drinking. Yes, I've seen you. Stop it.