Christmas ushers in an unending song that begin 700 years before the first Christmas in response to the prophecy of a child being born to us, a son being given to us (9.6) in Isaiah 12.1-6.  Then we hear the song continue as the angels appear to the shepherds at the birth of Jesus when the angels declared and sang in Luke 2.10-14.  Then we see that this song will be sung in the future by the church in the New Heaven and Earth in Revelation 19.1-7.  This is an un-ending song that will be sung forever – it is the song of Christmas.