Complete Encyclopaedia of Music/A/Agnus dei

Agnus dei. A prayer of the Romish liturgy, generally sung before the communion, and, according to the regulation of Pope Sergius H., in 688, at the close of the mass. Most of the great mass composers, as Mozart, Haydn, Beethoven, Hummel, Cherubini, &c., have employed all their depth and tenderness of melody and harmony in this portion of the mass.