The Graduale Romanum suggests "Afferentur regi... proximae," p. 504, for the Jan. 21 St. Agnes Offertory chant. I found a shorter one next to it, p. 505, with a shorter version of the text (the "minor" version; for students to sing, transcribed in modern notation, sorry). However, in my Triplex, the A of Afferentur is bracketed and seems to be replaced with an O, for Offerentur. The Vulgate (Ps. 45 (44): 15) gives, "Adducentur regi virgines post eam; proximæ ejus afferentur tibi." How would I go about determining what is most suitable for the liturgy, if there is a best choice?
From what I've observed of the Triplex, it seems that in addition to the rhythmic signs, it also gives the textual variants found in the manuscripts which are being used to provide the neumes. This is no doubt useful if you are being scholarly, but I wouldn't think that they are meant to be used liturgically; at any rate, they don't appear in the non-Triplex books.
I went and looked up the reference and sure enough 'offerentur' is the way the text goes in Einsiedeln 121 p. 47, so there's our historical variant.
With regard to the two different chants, I'd go with "Afferentur major", as this is what's given in the traditional books such as the Liber Usualis and the Vatican Edition of the Graduale Romanum.
But actually, looking it up in the Triplex, the chant being referenced is the "major" one, as it says "Afferentur regi... proximae, 504 ".
Contrast with the feast of St. Agatha, which calls for the offertory "Afferentur... post eam, 505 ".
By itself the first reference is not as specific as it could be (although the page number is distinction enough); however, when you compare with the second reference, it is clear that the "major" chant is the one being given as the offertory for the feast of St. Agnes.
I did realize that it was suggesting the Major one, and then I got distracted by the shorter Minor one. That got me off track, so it is good to be reminded that I had selected the wrong one (I didn't think to check for whom the Minor one was prescribed).
However, I don't think my students can tackle the Major one yet, if even the Minor one. Does it seem like it would be wrong to use the Minor one, since it is so close textually to the proper Major antiphon?
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