High Quality Content by WIKIPEDIA articles! The Songs of the Sabbath Sacrifice, also referred to as the Angelic Liturgy, are a series of thirteen songs, one for each of the first thirteen Sabbaths of the year, contained in fragments found among the Dead Sea scrolls. The Songs were found in 10 fragmentary copies: nine at Qumran (4Q400–407; 11Q17) and one at Masada. The dating is difficult to determine, but it is thought to have been written around 100 BCE.