Today is the Jewish High Holy Day of Atonement. It begins at sunset. They have a well-loved hymn sung on this day, the Kol Nidre, which means "All Vows." It's a prayer for release from any vows made to God and left unfulfilled. Sometimes, especially since World War II, it has come to refer especially to baptismal vows made under duress. I think the hymn is quite beautiful, and except for a certain plaintive quality some say is characteristic of Jewish music, it reminds me some of Russian Orthodox chant. Go here to hear a very good recording of it.