Agnus Dei (Barber) Agnus Dei (Barber) Agnus Dei (Lamb of God) is a choral composition in one movement by Samuel Barber, his own arrangement of his "Adagio for Strings" (1936). In 1967, he set the Latin words of the liturgical Agnus Dei, a part of the Mass, for mixed chorus with optional organ or piano accompaniment. The music, in B-flat minor, has a duration of about eight minutes. Barber's "Adagio for Strings" began as the second movement of his String Quartet, Op. 11, composed in 1936. At the request of Arturo Toscanini, he arranged it for string orchestra, and in January 1938 sent
Agnus Dei (Barber) a slow succession of chords, repeating "dona nobis pacem" in homophony in very low register, modulates to distant keys such as C major and F major. After another silence, a kind of recapitulation begins with the soprano and tenor singing the melody in unison on "Agnus Dei ... dona nobis pacem", while alto and bass counter with "miserere nobis". In the final line, the alto broadens the beginning of the melody to a last "dona nobis pacem", marked "mf molto espr. sost." (medium strength, very expressive and sustained), while the other parts end on a very soft "miserere nobis", marked