Ave Verum Corpus by William Byrd.

Text:
"Ave verum Corpus, natum de Maria Virgine:
vere passum immolatum in cruce pro homine:
cujus latus perforatum, unda fluxit sanguine:
esto nobis praegustatum in mortis examine
O Jesu dulcis, O Jesu pie, O Jesu fili Mariae,
miserere mei, Amen"

"Hail, true body, born of the Virgin Mary,
Who has truly suffered, was sacrificed on the cross for mortals,
Whose side was pierced, whence flowed water and blood
Be for us a foretaste (of heaven) during our final examining
O Jesu sweet, O Jesu pure, O Jesu, son of Mary
Have mercy upon me. Amen."