Today is the Feast of Corpus Christi, a feast in honor of the Holy Eucharist, born from the visions of a thirteenth century French Augustinian nun named Juliana of Liege. Her vision was of a darkness in the otherwise full moon. Juliana understood the moon to be the church and the darkness to be the result of there not being a feast in honor of the Blessed Sacrament. Her bishop heard her and believed her and instituted the first celebration of this feast, known as Festum Eucharistiae, at the church of Saint-Martin in 1247. (Much more about today’s feast and how to live it in your home here.)
If this all sounds rather like Holy Thursday to you, then you’ve been paying attention. In many ways, today’s feast is a duplicate of the one in Holy Week, but without any of the somber notes. They both conclude with processions in which the consecrated Host, reserved from the Mass just celebrated, is carried to a place of veneration and repose.
Perhaps the best way to understand how these feasts are linked is to consider the famous hymn by St. Thomas Aquinas, known popularly by its Latin name, Pange lingua. Most of us sing the hymn on Holy Thursday, often both in Latin and in English translation. It is probably the hymn most often associated with the advent of the Triduum, or the Three Days, which begin with Mass on Thursday in Holy Week and end at the beginning of the Easter Vigil on the following Saturday.
But Aquinas didn’t write Pange lingua for Holy Thursday. He wrote it, and two other hymns for the Feast of Corpus Christi, at the invitation of Pope Urban IV, the pope who had earlier served in Liege and had helped establish the feast there.
Verbum caro, panem verum,
verbo carnem efficit,
fitque sanguis Christi merum,
et, si sensus deficit,
ad firmandum cor sincerum
sola fides sufficit.
Tantum ergo sacramentum
et antiquum documentum
novo cedat ritui;
praestet fides supplementum
Word made flesh, by word he maketh
very bread his flesh to be;
man in wine Christ’s blood partaketh,
and if sense fail to see,
faith alone the true heart waketh
to behold the mystery.
Therefore we, before it bending,
this great sacrament adore;
types and shadows have their ending
in the new rite evermore;
faith, our outward sense amending,
maketh good defects before. (translation by John Mason Neale 1851)