For several years, many traditional choir directors have refused  to sing Away in a Manger because they think it was written by Luther.  A bit of detective work done by researchers at the US Library of Congress finds Luther was not the author.  Further, regardless of who the author is, there is no heresy contained within the stanzas but only a sweet song about baby Jesus.

    Here is a bit of history about the song from a Protestant site:
     
    History of Away In A Manger

    No, Away In A Manger was NOT written by Martin Luther. The confusion came when James R. Murray published the song in a popular children's songbook as Luther's Cradle Hymn (Composed by Martin Luther for his children and still sung by German mothers to their little ones.) Since the general public took the title at its word and passed it on, the myth continues today. Ironically, the song is virtually unknown in Germany and bears no resemblance to Luther's musical style. In truth, the words came from a poem found inside a Lutheran Sunday school book published in 1885. Where? Not Germany, but Philadelphia, PA USA! James R. Murray may have written the song himself. For certain, Martin Luther did not write this song. Sorry about that! We appreciate the detective work of researchers of the US Library of Congress in uncovering this information.