This is an anonymous c19 text supposedly based on Isaiah 7:14 set to VENITE ADORAMUS.
To be picky it is actually a hymn based on traditional sources from outside the canon that create an aural nativity scene for those in cold climates in the Northern hemisphere. The snow only lays on the ground in a particular localised imagination and the song is out of time and place in the heat of a Southern Christmas.
OCP sell the sheet music but it is PD.
1.
The snow lay on the ground,the stars shone bright,
When Christ our Lord was born
on Christmas night.
Veníte, adorémus Dóminum,
Veníte, adorémus Dóminum.
Refrain
Veníte, adorémus Dóminum,Veníte, adorémus Dóminum.
2.
’Twas Mary, Virgin pureof holy Anne,
That brought into this world
the God made man.
She laid him in a stall at Bethlehem;
The ass and oxen shared the roof with them.
3.
Saint Joseph, too was nearto tend the child;
To guard him and protect
his mother mild:
The angels hover’d ’round, and sang this song:
Veníte, adorémus Dóminum.
4.
And thus that manger poorbecame a throne;
For he whom Mary bore
was God the Son.
O come, then, let us join the heav’nly host,
To praise the Father, Son, and Holy Ghost.