The Advent Prose's Authorship

It seems unlikely that Prudentius (348-after 405, possibly c.413) compiled the Advent Prose Rorate cæli desuper, not least because St Jerome (c. 347-420) had only finished translating the Vulgate in 405, and the Advent Prose quotes the Vulgate (almost) word-for-word, while the Vulgate itself took some time in becoming accepted in the West; furthermore, the fourth stanza of the Prose, beginning Consolamini, quotes word-for-word from the first Responsory of Matins of the Second Sunday of Advent (omitting only Jerusalem and et liberabo te), and it is implausible that what became the Roman Breviary was already substantially in existence at the start of the fourth century.

Another candidate author for the Advent Prose is Pierre Cardinal de Berulle (1575-1629), founder of both the French Oratory (in 1611) and the so-called 'French School' of spirituality, a noted mystic.  However, I have yet to locate the Rorate cæli among his works. Instead, the third, less well-known candidate, seems the most likely: Father Bourget of the French Oratory, to whom are attributed both text and music. Some sources date his work to 1634, but others – especially the Franciscan Processional used at the Holy Sepulchre – to the year 1615.

If indeed the good Oratorian Père Bourget produced this plaintive composition in or about 1615, but shortly after the establishment of the Oratory of France by de Berulle, it is entirely possible that the latter's spiritual doctrine inspired the former. While I am more familiar with French Baroque music of the generations after this early date, I am aware that long Scriptural compilations set to music were quite rightly esteemed and produced at this period, and thus the sensibility of the Prose seems to fit this timeframe.

While at Paris at that time the old Parisian Breviary was still in use (not to be confused with the Neo-Gallican Paris Breviary later imposed in the early eighteenth century), this I expect would have been comparable, and indeed was increasingly being comformed, to the model of the Breviary, that is, the Roman, then newly reformed by order of the Council of Trent. I have therefore noted below not merely the Scriptural sources of the Prose, but also the passages of the Roman Breviary that if anything even more closely match to it:

THE ADVENT PROSE

R/. Rorate cæli desuper, et nubes pluant justum.

[Is 45:8ab (versicle at Adv. Vespers, & Lauds Aña. 1, Tue. before Christmas Vigil, Brev. Rom.)] 

1. Ne irascaris Domine, ne ultra memineris iniquitatis: ecce civitas Sancti facta est deserta: Sion deserta facta est: Jerusalem desolata est: domus sanctificationis tuæ et gloriæ tuæ, ubi laudaverunt te patres nostri.

[Is 64:9a,b,10,11ab – abbrev. of Lectio iii, 4th Adv. Thu. (Brev. Rom.), except tuæ for nostræ in both places] 

2. Peccavimus, et facti sumus tamquam immundus nos, et cecidimus quasi folium universi: et iniquitates nostræ quasi ventus abstulerunt nos: abscondisti faciem tuam a nobis, et allisisti nos in manu iniquitatis nostræ.

[Is 64:5c; Is 64:6a,cd,7cd – abbrev. of Lectio ii, 4th Adv. Thu. (Brev. Rom.), except tamquam for ut] 

3. Vide Domine afflictionem populi tui, et mitte quem missurus es: emitte Agnum dominatorem terræ, de petra deserti ad montem filiæ Sion ut auferat ipse jugum captivitatis nostræ. 

[Abbrev. of R/. iii. 1st Adv. Fri., Brev. Rom. (cf. Ex 3:7a; Ex 4:13b); Is 16:1 (Lauds Aña. 2, Tue. before Christmas Vigil, Brev. Rom.); cf. 14:25d; cf. var.] 

4. Consolamini, consolamini, popule meus: cito veniet salus tua: quare mœrore consumeris, quia innovavit te dolor? Salvabo te, noli timere, ego enim sum Dominus Deus tuus, Sanctus Israël, Redemptor tuus. 

[Is 40:1a (abbrev. of Bened. Aña, 4th Adv. Thu.); abbrev. of R/. i of 2nd Sun. of Adv. (cf. var.; cf. Micah 4:9a,d; cf. var.; cf. Is 43:3ab)]

It is amusing that the English version adapted for Anglican use replaces the third verse with another, taken directly from the King James version of Isaiah 43:10a,11,13b (verses not read at all during Advent in the Roman Breviary) —

Ye are my witnesses, saith the Lord, and my servant whom I have chosen; that ye may know me and believe me: I, even I, am the Lord, and beside me there is no Saviour: and there is none that can deliver out of my hand.

This variant has now been accepted into Catholic communion, as it is given in the new Customary of Our Lady of Walsingham. For amusement's sake, I have rendered this into Latin, using the Vulgate:

Vos testes mei, dicit Dominus, et servus meus quem elegi: ut sciatis, et credatis mihi, Ego sum, ego sum Dominus, et non est absque me salvator: et non est qui de manu mea eruat.