Stabat Mater is a thirteenth century Roman Catholic sequence attributed to Jacopone da Todi. It has been set to music by many composers, among them Haydn, Dvorak, Vivaldi, Rossini, Pergolesi, Stanford, Gounod, Penderecki, Poulenc, Szymanowski, Alessandro Scarlatti (1724), Domenico Scarlatti (1715), Pedro de Escobar, Arvo Pärt and Giuseppe Verdi. Its title is an abbreviation of the first line, Stabat Mater Dolorosa ("The sorrowful mother was standing"). The hymn, one of the most powerful and immediate of medieval poems, meditates on the suffering of Mary, Jesus Christ's mother, during his crucifixion.

Karl's setting extends this to a universal depiction of grief by using ancient text from the area (Holy Land/Middle East) that will be sung in Hebrew, Greek and Aramaic (the lingua franca of the period) and a contemporary poem, sung in English. The orchestration includes instruments indigenous to the area, percussion such as the darbuka & riq and the woodwind duduk.