who composed it?
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matthew mark luke john bless the bed that i lay on It  is an English children's bedtime prayer and nursery rhyme.
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Matthew, Mark, Luke and John [SEP] Origins
The verse may be one of few English nursery rhymes to have ancient origins. The Babylonian prayer "Shamash before me, behind me Sin, Nergal at my right, Ninib at my left", is echoed by the medieval Jewish prayer: "In the name of the Lord, the God of Israel, may Michael be at my right hand; Gabriel at my left; Uriel before me; Raphael behind me and the Shekhinah of God be above my head" which is used as a prayer before sleep. A Christian version has been found for Germany at the end of the Medieval period. However, the first known record of the lyrics in English is from Thomas Ady's witchcraft treatise "A Candle in the Dark, or, a treatise concerning the nature of witches and witchcraft" (1656), which tells of a woman in Essex who claimed to have lived in the reign of Mary I (r.