This edition is based on two sources, namely Librone 1, ff. 145v–147r (copied by Scribe A) and Librone 3, ff. 126v–127r (copied by Scribe I).
The scribes were not particularly attentive to the spelling in this motet and inserted some mistakes: the scribe forgot the word ‘salus’ at first in Librone 1, B and had to add it above the line, forgot the final a in ‘gracia’ in Librone 1, C, T2 and B, made ‘verbi’ out of veri in Librone 1, T1, and wrote ‘gaudium’ instead of gaudia in Librone 1, T2 and in Librone 3, T1. In Librone 3 we also find grammatical and orthographical variants, like ‘laudantem’ for laudantium in all voices of Librone 3. ‘Digneris visere’ (‘May you deign to behold us’) becomes ‘dignaris viscere’ (‘through the womb you deem worthy’) in Librone 3, C and T1.
In this motet too the subject is Mary and her role as mother of Christ and intercessor for mankind. She reached Heaven by giving birth to the Saviour (verses 2, 3, and 4) and is now invoked by the faithful – who are here defined as ‘sick’ (infirmi), ‘miserable’ (miseri) and polluted by sins (sordes peccatorum) – to be their intercessor before God and allow them to ascend to Heaven as well.
In this case, as in many other instances in the cycle, the motet was composed as a compilation of verses from different Marian sequences (Ave caelorum regina, AH 54, no. 275, p. 416, verses 5 and 4; Salvatoris mater pia, AH 54, no. 280, pp. 424–26, verse 5; Verbum bonum et suave, AH 54, no. 218, pp. 343–45, verse 3; Ave virgo virginum, AH 54, no. 285, pp. 432–33, verses 9–10). Verses 1 and 2 of the motet are also transmitted as prayers and can be found in books of hours or private prayer books. Two fifteenth-century manuscripts, for instance, transmit a prayer in which verses 1 and 2 of the motet are switched in order, but literally adopted as a prayer text:^[1] these sources are a book of hours from Parma (Bibl. Palatina, MS Parm. 1346 [S. Quintino, 1498], f. 85v) and a book of hours following the use of Rome (Paris, BnF, MS Lat. 1157, f. 18v).^[2] The texts transmitted there read as follows:

It is also plausible to think that Compère knew this text from such sources, and did not necessarily draw it directly from the sequence.

^[1] See Giacomo Baroffio, ‘Corpus italicum precum: Materiali per una storia del sentimento religioso in Italia’, http://www.hymnos.sardegna.it/iter/iterliturgicum.htm.

^[2] See also Victor Leroquais, Les livres d’heures manuscrits de la Bibliothèque nationale, 3 vols. (Paris: n.p., 1927), I: 70–72, no. 22.