Is to specify Jesus Christ (whose name was removed from the traditional Latin table blessing that is the film’s one spoken prayer) automatically to “preach to the choir”?
I had to look up what he's talking about here. They shortened the whole prayer, not just removed or changed a word as he's suggesting. Apparently they only said "Bless us, O Lord, and these Thy gifts. Amen."
As it was in Latin, the chances of even 0.1% of the audience noticing is slim.