This motet for the Festival of Christmas by Giovanni Gabrieli (1555–1612) was composed for an eight-part chorus with accompanying instruments doubling the choir. It may be performed unaccompanied, accompanied by keyboard alone, or brass quartet and organ. In performance this polychoral and antiphonal music is more effective if the two choirs are placed at some distance from each other. This technique was made much use of by Gabrieli and his successors at St. Mark's Cathedral in Venice, where the composer was organist. Edited by S. Drummond Wolff.