Why does the Battle Hymn of the Republic say Jesus was born "in the beauty of the lillies"? A seldom-quoted stanza of the "Battle Hymn of the Republic" says 


  In the beauty of the lillies Christ was born across the sea
  with a beauty in his bosom that transfigures you and me.
  As he died to make men holy, let us die to make men free,
  while God is marching on.


My question is, what does it mean when it says that Jesus was born "in the beauty of the lillies"?  I thought the story was that he was born in a manger, not among lillies.  Is there any reference to lillies in the Biblical description of Jesus' birth?

Or does the "in" mean "with", i.e. is it saying that Jesus was as beautiful as a lily when he was born?  That could be a reference to the line in the Bible about how King Solomon was not arrayed so finely as the lillies of the field.
According to this site, the first draft of the song actually had the words


  In the whiteness of the lilies he was born across the sea


And then the final version of the song, which was first published in 1862 had the words


  In the beauty of the lilies Christ was born across the sea


That same site references a book by Edmund Wilson entitled Patriotic Gore: Studies in the Literature of the American Civil War (New York: Oxford University Press, 1966).  On page 96 of that book, the author suggests that the lyrics may be referring to Easter lilies (which are associated with the death and resurrection of Jesus).

Absent any reason given by Julia Ward for choosing those words, we can merely speculate as to why she chose them.  Based on the context, though, she was clearly wanting to convey the hope portrayed in Jesus' birth and the beauty of what He accomplished in stark contrast to the darkness underlying the rest of the song.