Sancte Dei, pretiose

You can read about this hymn from the Sarum Breviary, Sancte Dei, pretiose, at the Hymns and Carols of Christmas website, which also has a MIDI file of the melody.

The day of Saint Stephen falls on December 26.

Sancte Dei, pretiose

1. Sancte Dei, pretiose,
Protomartyr Stephane,
Qui virtute caritatis
Circumfulsus undique,
Dominum pro inimico
Exorasti populo

(Saint Stephen)

Illuminare, Jerusalem

I would urge everyone who is interested in learning more about this song to read this VERY informative blog post by "a clerk of Oxford."

Illuminare, Jerusalem

Only the refrain of the song is in Latin, much like the "gloria in excelsis Deo" refrain used in Angels We Have Heard on High. The song itself is from a 16th-century poem in Scots. Here is the first verse; see the blog post for additional verses:

1. Jerusalem reioss for joy: 

Jesus the sterne of most bewte 

In thee is rissin, as rychtous roy, 

Fro dirknes to illumyne the. 

With glorius sound of angell gle 

Thy prince is borne in Baithlehem 

Quhilk sall thee mak of thraldome fre. 

Illuminare, Jerusalem.