O admirabile commercium (motet cycle) (Loyset Compère)
Lynn Halpern Ward (The "Motetti Missales" Repertory Reconsidered, Journal of the American Musicological Society, Vol. 39, No. 3 – Autumn 1986) has suggested that this selection of works by Loyset Compère contained in the four Libroni (large choirbooks) from the library of Milan's Duomo may form part of a motetti musicali cycle: a Milanese practice of substituting the movements of a mass with motets.
In the Libroni, the works are grouped as follows:
- Librone 1: Ave virgo gloriosa — Ave regina caelorum — O admirabile commercium
- Librone 2: Sanctus & O sapientia — Ave virgo gloriosa
- Librone 3: O genitrix gloriosa
- Librone 4: O admirabile commercium — Sanctus (without O sapientia) — Suscipe verbum ( = O genitrix gloriosa)
In some of the known motetti musicali cycles, the Sanctus is the one regular mass movement which remains, and it is followed by a simple homophonic piece, to be performed at the Elevation. The setting of O sapientia which follows the Sanctus in Librone 2 appears to be intended for use as such an Elevation motet. There is a clear indication that it should be followed by the next piece, Ave virgo gloriosa, presumably as a post-Elevation motet, which provides the final resolution.
In Librone 3, O genetrix gloriosa is not grouped with other motets, but follows settings of the Gloria and Sanctus (a different setting from that in Ward's cycle), and may have been intended for use with them.
Librone 4 was badly damaged in a fire while on display at the 1906 Espositzione Internationale in Milan. The setting Suscipe verbum in this book is a reworked version of O genetrix gloriosa. The beginnings of its upper two voices have been lost.
O genetrix gloriosa and Ave virgo gloriosa also appear in Petrucci's Motetti A, combined to form a 2-part motet. The same pairing may be found in a number of other sources.
Whether or not all the components of Ward's proposed cycle were ever performed as a unit, it seems likely that they were used in the groupings in which they appear in the Libroni.
Jean Richafort based a mass on O genetrix gloriosa.