“The Sussex Carol” appeared in 1684 in a collection called A Small Garland of Pious and Godly Songs. The author is unknown, but may have been a Catholic Bishop in Ireland in the 1500s or 1600s. The version we sing today was harmonized by Ralph Vaughan Williams, one of Britain’s most prominent serious composers of more resent days (1872-1958).
On Christmas night all Christians sing,
To hear the news the angels bring;
On Christmas night all Christians sing,
To hear the news the angels bring;
News of great joy, news of great mirth,
News of our merciful King’s birth.
Then why should men on earth be sad,
Since our Redeemer made us glad:
Then why should we on earth be sad,
Since our Redeemer made us glad:
When from our sin He set us free,
All for to gain our liberty.
When sin departs before Your grace,
Then life and health come in its place;
When sin departs before Your grace,
Then life and health come in its place;
Angels and men with joy may sing,
All for to see the newborn King.
All out of darkness we have light
Which made the angels sing this night;
All out of darkness we have light
Which made the angels sing this night:
“Glory to God and peace to men,
Now and forevermore. Amen.”
Working out Salvation with Fear and Trembling 
The men in our choir sang an arrangement of this song in our Christmas concert at ICBC this year. I was not familiar with this song prior to practicing it but I really like it.
Glad you enjoyed it Bob. I have not heard it yet but love the words. I wish I could have been there to here you guys sing it!