As in the first Kyrie, Obrecht here includes the complete suffrage antiphon O beate pater Donatiane as the tenor cantus firmus, now restored to its original pitch level. At the same time, however, he weaves in a second pre-existent text and melody, the Dutch song Gefft den armen gefangen umb got, Which requests alms for poor prisoners and thus recalls the charitable projects of Donaes do Moor, especially his donation to the donckercamer, or debtor’s prison, specified in his will. This brief Dutch song is heard twice in the alto voice, and then migrates to the bass voice to conclude the Kyrie.
For more information, see:
Hiley, David. Western Plainchant: a Handbook. Oxford: Oxford University Press. 1993. See in particular pp. 150-56, 211-13.
Crocker, Richard L. “Kyrie eleison.” Grove Music Online. 10 Jul. 2018. www.grovemusiconline.com
Strohm, Reinhard. Music in Late Medieval Bruges. Oxford: Clarendon Press. 1985. See in particular pp.38-42.
Wegman, Rob C. Born for the Muses: The Life and Masses of Jacob Obrecht. Oxford: Oxford University Press, 1994. See in particular pp.169-74.