Q: A confrere asked if it’s possible to use one of the Sunday’s prefaces on an ordinary weekday. Another question – this one from me: Is is permissible to use a “proper” preface with one of the forms of the Euch Prayer V? I would think not.
A: I’ll say yes to Sunday prefaces on weekdays because of the way that GIRM 365b speaks about prefaces that go with Eucharistic Prayer II. That prayer is appropriate for weekdays, and may be used with “other Prefaces” – without excluding the ones for Sundays.
Prayer V comes with four variations, each with its own preface. When it first came out in English in 1991, it carried an introduction that said, “This eucharistic prayer with its proper prefaces and corresponding intercessions may be used with the formularies of the Masses for Various Needs and Occasions, which do not have their own proper preface.”
That introduction did not carry over into the 2000 missal, and I don’t have the Latin original of the sentence I quote above, but the word “which” in the last line would certainly be better translated as “that” because some of the formularies DO have their own proper preface.
I still think the sentence above offers an idea of how the prayers were intended. The four versions were given their own preface, which is not to be replaced with another. If you need a different preface, then you probably need a different eucharistic prayer.
I know priests who use other prefaces with Prayer V, but I don’t think that was the idea.