This short Eucharistic hymn dates to the 14th century, and has sometimes been attributed to Pope Innocent VI (d 1362).
Ave, verum corpus, natum de Maria Virgine: vere passum, immolatum in cruce pro homine: cuius latus perforatum unda fluxit et sanguine: esto nobis praegustatum, in mortis examine. O dulcis, O pie, O Jesu, Fili Mariae. Miserere mei. Amen.
Translation: Hail the true body, born of the Virgin Mary: You who truly suffered and were sacrificed on the cross for the sake of man. From whose pierced side flowed water and blood: Be a foretaste for us in the trial of death. O sweet, O gentle, O Jesu, son of Mary, have mercy on me. Amen.
William Byrd’s setting of this text was written to celebrate the Feast of Corpus Christi, which had been outlawed in England in 1548 following the Reformation. But Roman Catholics still surviving in England still celebrated the feast secretly, sometimes more brazenly.
Kerry McCarthy (in her book Byrd) writes that Corpus Christi had been an especially festive holy day before the clamp-down on popish rituals commenced. “Medieval parishes had celebrated it with lavish floral displays and elaborate outdoor processions [of the Blessed Sacrament], and this sort of activity continued even after Catholic worship became illegal in England.”
Byrd wrote a dozen pieces for this festival, Ave verum corpus being the best-known.
Read an account here of the role of Andrew Carnegie in reviving access to Byrd’s Ave verum corpus in the 1920s.
Here is a performance of Byrd’s Ave verum corpus by The Tallis Scholars.