there are actually two different sets of lyrics to that song.
The secular is called "Carol of the Bells".
Hark how the bells
Sweet silver bells
All seem to say
Throw cares away
Christmas is here
Bringing good cheer
To young and old
Meek and the bold
Then there is the religious version, called "Ring Christmas Bells".
Ring, Christmas bells!
Merrily ring!
Tell all the world
Jesus is King!
Loudly proclaim,
with one accord,
the happy tale!
Welcome the Lord!
This may sound morbid, given it's the religious version, but every time I hear this, I think it sounds like background music to a Christmas horror movie, with a panicked person running from a pursuer.