Corpus Christi

Corpus Christi — the Solemnity of the Most Holy Body and Blood of Christ — is kept on the Thursday after Trinity Sunday, in many places transferred to the following Sunday. Instituted for the universal Church by Pope Urban IV in 1264, the feast was prompted by the Eucharistic miracle of Bolsena, where in 1263 a Bohemian priest, doubting the Real Presence, found the host bleeding onto the corporal during Mass. The blood-stained corporal is still kept in the Cathedral of Orvieto, to which Urban IV carried it.

The Bull of institution, Transiturus de hoc mundo, was composed by St. Thomas Aquinas at the Pope's request, and Aquinas also wrote the office and Mass texts — among them the Pange lingua, the Verbum supernum prodiens, and the Tantum ergo Sacramentum — that the Church still sings at Exposition and Benediction. The Corpus Christi procession, in which the Blessed Sacrament is carried through the streets under a canopy, became one of the most public devotions of medieval Christendom.

At Orvieto the corporal is displayed in the Chapel of the Corporal in the Duomo, and the feast is still kept with a great procession through the steep streets of the town. From Cologne to Kevelaer to the smallest Italian village, the procession winds out of the church and back, the Blessed Sacrament carried under the sky to bless the fields and the houses it passes.