Hark! what mean those holy voices. J. Cawood. [Christmas.] This popular hymn appeared in 1819 in the 8th edition of Cotterill's Selection, No. 269, in 6 stanzas of 4 lines, with the refrain, "Hallelujah." In common with all the hymns in that Selection it was unsigned; but when republished by J. Montgomery in his Christian Psalmist, 1825, it was attributed to "Cawood." In some works, and collections, it is dated 1816; but in J. Cawood's son's correspondence with D. Sedgwick, it is undated [S. MSS.], and failing further information, it mutt remain as 1819. Of all Cawood's hymns this is the most popular. It is in extensive use in Great Britain and America. Original text in Snepp's Songs of Grace & Glory, 1872, No. 205, with "glory sing" for "praises sing" in stanza iv., line 2.
--John Julian, Dictionary of Hymnology (1907)