The fifth motet in Compère’s cycle Hodie nobis de virgine was edited according to Librone 1, ff. 175v–176r, the only source for this piece. The scribe (Scribe A) copied it without mistakes or divergent spellings. This is not surprising, since the texts utilized by Compère for this piece are extremely well known, comprising the Sanctus from the Ordinary of the Mass and part of an antiphon for Christmas (Cantus ID 005362).
Although in this case the loco rubric is missing, the topic of this motet clearly signals that we are dealing with a Sanctus–ad Elevationem piece, which accompanied the performance of the Sanctus and the consecration and elevation of the host:^[1] the Sanctus that was textually integrated in the motet was sung as the culmination of the preface and just before the celebrating priest began with the Canon missae; furthermore, the text of the second half of the motet describes the Eucharistic mystery exactly (‘Verbum caro factum est’ / ‘The word was made flesh’) and refers to the situation of the faithful attending the ritual (‘et vidimus gloriam eius’ / ‘and we saw his glory’).

^[1] See Agnese Pavanello, ‘The Elevation as Liturgical Climax in Gesture and Sound: Milanese Elevation Motets in Context’, Journal of the Alamire Foundation, 9/1 (2017), 33–59: 42.