I have this from the Oxford Book of Carols - Tim Radford.

***************************************

THE BOYS CAROL - (Personent Hodie)

Sing aloud, on this day, Children all
Raise the lay, cheerfully we & they
Hasten to adore thee, sent from highest glory
For us born, born, born x 2
For us born on this morn, of the Virgin Mary

Now a child he is born swathling bands him adorn
Manger bed he'll not scorn, Ox & ass are near him
We as Lord revere him
And the vain. vain, vain x 2
And the vain powers of hell,
Spoiled of prey now fear him.

From the far Orient, guiding star
Wise men sent, Him to seek
There intent, Lord of all creation
Kneel in adoration.
Gifts of gold, gold, gold x 2
Gifts of gold, frankincence
Myrrh for their oblation.

All must join him in praise,
men & boys voices raised,
On this day of all days,
Angels voices ringing, Christmas tidings bringing.
Join we all, all, all x 2
Join we all Gloria In Excelsis singing.

Piae Cantiones 1582
Words & Trans. Oxford Book of Carols.