This new, original work is based on the 11th-century responsorial chant for the Matins on Christmas Day: "O great mystery, and wonderful sacrament, that animals should see the newborn Lord, lying in a manger!" The text is printed above the handbell staves to give ringers and directors a creative and musical frame of reference. Handchimes weave in and out through the piece, while the simple yet soaring melody and rich, poignant harmonies convey the beauty and mystery of the birth of the Savior. O Magnum Mysterium is certain to be one of the more moving and profound additions to the Christmas handbell repertoire.