The Eucharist may also be meant by “our daily bread” in the Lord’s Prayer, Matthew 6:11; Luke 11:3.
Well, only in a figurative way. And if this is a reference to Jerome’s
supersubstantialis (cf. “give us this day our supersubstantial bread” in the
version of Matt 6:11Douay-Rheims Bible), then I thik that you have been misled. This probably rests upon a misunderstanding of the latin word
supersubstantialis. One assumes, because of the
substantialis, that
St. Jerome (who produced the Vulgete translation) had the Eucharist in mind. And perhaps he did, in a figurative way. But that is another matter entirely.
I agree that on some level this is a reference to the Eucharist, since it is talking about bread. (This would be a spiritual reading of the text.) But neither the latin
supersubstantialis nor the greek
ἐπιούσιος (
epioúsios) is a reference to transubstantiation. According to
BDAG, there is some doubt as to what
ἐπιούσιος means, but the three most probable possibilities is these: (1) [bread] that is
necessary for existence; (2) [bread]
for the current day, for today; or (3) [bread]
for the next day.
I think that the first reading is the best one, seeing the Greek adjective ἐπιούσιος as derived from the preposition
ἐπί (’at, over, to,’ etc.) + the noun
οὐσία (‘being, existence’). This is reflected in the Vulgate’s
panis supersubstantialis. That doesn’t, however, have anything to do with transubstantiation. It just means the bread
needed for existence; needed to uphold one’s ‘substance.’ In one of the shows at Catholic Answers Live, Jimmy Akin said that
supersubstantialis had nothing to do with transubstantiation, and that the best rendition of it in English was ‘life-sustaining.’
So a good translation might go something like this: “Give us this day our life-sustaining bread.”
That doesn’t mean, however, that one cannot interpret ‘give us this day our daily bread’ in a spiritual way, referring to the Eucharist,
in addition to a literal reading. But that is a spiritual reading of the text, a reading that should not trump a literal reading.