Vigil Masses, in the Roman Rite, are typically threshold points. We are quite there, but not quite there yet. A vigil Mass is an oxymoron. Something bittersweet. And, for the Easter Vigil, the flow typically expresses this sort of split personality. The sorrow of Lent, broken once on Maundy Thursday, finally dissipates on Holy Saturday, partially when the Gloria is sung once again, and fully when the Alleluia returns for good. But, even so, after the Alleluia is sung, that sweet song of praise of God, we then sing a gradual in the tone of the Lenten canticles and tracts, that bitter and prolonged cry to God in penitential seasons.
Between the 10th and 12th centuries, the Church’s longing for the joy of the alleluia enabled Her cantors to prolong the chanting in a melismatic iubilus, which eventually admitted a variety of texts, which consequently evolved into prosae or sequentiae in their own right. Aquitaine in France produced four for the Easter Vigil (Iubilate Deo, omnis arva; Iam turma coelica laeta; Hoc pium recita plebs; Omnes, iubilate cordeque laetate), and one for the Pentecost Vigil (Pangamus carmina). Benevento in Italy produced another in two versions, one being longer than the other, for the Easter Vigil, Lux de luce. The region of Ravenna, on the other hand, also in Italy, produced its own musical incarnation of the apparently longer Beneventan version.
The Aquitanian exemplar, whose source manuscript is Paris lat. 903 (Gradual of St. Yrieix), folio 76v, features a long melisma that is more prolix than what we are privileged to sing nowadays. The longer Beneventan version, on the other hand, draws source from the manuscript Benevento MS VI.34, folio 112r. Finally, the Ravennate version, we are informed, is found in Padua MS A.47, folio 129. This manuscript is dated 11–12th century, but the chant itself has been dated to as early as the 8th century, in parentheses at the moment while conclusive evidence remains forthcoming.
In 1971, Dr. Kenneth Levy transcribed the manuscripts and published a critical study of the sequence. From his transcriptions, we produced a copy in Gregorian notation (click on the image to access the file), taking the liberty to add an Amen and an Alleluia at the end (it is a sequence, after all). While resurrecting this sequence in its proper place, both in the vetus and novus ordo, will no doubt be termed patent antiquarianism, chanting it after the offertory or during Holy Communion will doubtless allow us to savour its powerful message of joy and hope.
Ut in omnibus laudetur Dominus.
 Kenneth Levy, Lux de luce: the origin of an Italian sequence: MQ 57 (1971) pp. 40–61.
 Kenneth Levy, Ravenna chant: GMO (https://doi.org/10.1093/gmo/9781561592630.article.22963).