Q: In the Order of Mass, just before communion, why does the priest say those are blessed who are invited to “the supper of the Lamb” and not to “the wedding supper of the Lamb,” as in Revelation 19:9?
A: I have been serving the meetings of the International Commission on English in the Liturgy since 2006, and when I started, most of the work on the Order of Mass had been completed, so I have no detailed notes on any discussion. But I can consult various versions of the developing revised translation from that period.
In all of the cases I have checked, I consistently see the same translation, even where the Revelation passage is footnoted. It has always been “the supper of the Lamb.”
The simplest answer to your question, then, lies within the Ordo Missæ itself. It uses the Latin word cena, so that is the word that ICEL translated. Even in the Vulgate, Revelation 19:9 concerns the “wedding supper” of the Lamb, but somehow the word for “wedding” was never included in the invitation to communion in the Order of Mass. One can speculate reasons—that Jesus instituted the eucharist at a Passover supper, that Catholic weddings used to take place apart from Mass, or that someone preferred brevity. All we know is that the word for “wedding” is not and has not been in the Order of Mass, so ICEL was not authorized to add it.