Prayer sung in Jewish synagogues at the start of services on the eve of Yom Kippur .
The prayer begins with an expression of repentance for all unfulfilled vows, oaths, and promises to God during the previous year. It was in use as early as the 8th century, perhaps as a means of annulling oaths forced on Jews by their Christian persecutors. The melody used by Ashkenazi Jews became famous when the composer Max Bruch used it in his Kol Nidrei (1880).