The Feast of Corpus Christi

Why is this day called Corpus Christi?

Because on this Thursday the Catholic Church celebrates the institution of the most Blessed Sacrament of the Altar. The Latin term Corpus Christi signifies in English, Body of Christ.

Who instituted this festival?

Pope Urban IV, who, in the decree concerning it, gives the following explanation of the institution and grandeur of this festival:

"Although we daily, in the holy Sacrifice of the Mass; renew the memory of this holy Sacrament, we believe that we must, besides, solemnly commemorate it every year, to put the unbelievers to shame; and because vie have been informed that God has revealed to some pious persons that this festival should be celebrated in the whole Church, we direct that on the first Thursday after the octave of Pentecost the faithful shall assemble in church, join with the priests in singing the word of God," &c.

Hence this festival was instituted on account of the greatness of the divine mystery; the unbelief of those who denied the truth of this mystery; and the revelation made to some pious persons.

This revelation was made to a nun at Liege, named Juliana, and to her devout friends Eve and Isabella. Juliana, when praying, had frequently a vision in which she saw the bright moon, with one part of it somewhat dark; at her request she received instructions from God that one of the grandest festivals was yet to be instituted the festival of the most Blessed Sacrament of the Altar.

In 1246, she related this vision to Robert, Bishop of Liege, who after having investigated the matter with the aid of several men of learning and devotion, among whom was Jacob Pantaleon, Archdeacon of Liege, afterwards Pope Urban IV made arrangements to introduce this festival m his diocese, but death prevented his intention being put into effect. After the bishop's death the Cardinal Legate Hugh undertook to carry out his directions, and celebrated the festival for the first time in the year 1247, in the Church of St. Martin at Liege.

Several bishops followed this example, and the festival was observed in many dioceses, before Pope Urban IV in 1264 finally ordered its celebration by the whole Church. This order was confirmed by Clement V, at the Council of Vienna in 1311, and the Thursday after the octave of Pentecost appointed for its celebration. In 1317, Pope John XXII instituted the solemn procession.

Why are there such grand processions on this day?

For a public profession of our holy faith that Christ is really, truly and substantially present in this Blessed Sacrament; for a public reparation of all the injuries, irreverence, and offences, which have been and are committed by impious men against Christ in this Blessed Sacrament; for the solemn veneration and adoration due to the Son of God in this Sacrament; in thanksgiving for its institution; and for all the graces and advantages received therefrom; and finally, to draw down the divine blessing upon the people and the country.

Had this procession a prototype in the Old Law?

The procession in which was carried the Ark of the Covenant containing the manna, was a figure of this procession.

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From Explanation of the Epistles and Gospels
by Fr. Leonard Goffine (c) 1880