Corpus Christi (in Latin, "Body of Christ") or Solemnity of the Body and Blood of Christ, formerly called Corpus Domini ("Body of the Lord"), is a feast of the Catholic Church destined to celebrate the Eucharist. Its main purpose is to proclaim and increase the faith of Catholics in the real presence of Jesus Christ in the Blessed Sacrament, giving him publicly the worship service (latria).
The celebration takes place on the Thursday following the Solemnity of the Most Holy Trinity, which in turn takes place on the Sunday following Pentecost (that is, Corpus Christi is celebrated 60 days after Easter Sunday). Specifically, Corpus Christi is Thursday that follows the ninth Sunday after the first full spring moon of the northern hemisphere.
The party arose in the Middle Ages, when in 1208 the religious Juliana de Cornillon promoted the idea of celebrating a festivity in honor of the body and blood of Christ present in the Eucharist. Thus, it is celebrated for the first time in 1246 in the Diocese of Liège (Belgium).
In the year 1263, while a priest celebrated the mass in the church of the town of Bolsena (Italy), when the consecrated Host broke, blood flowed, according to tradition. Science has tried to explain this event by attributing it to the probable presence in bread of the red pigment prodigiosina secreted by the bacterium Serratia marcescens. This fact, very widespread and celebrated, gave a definite boost to the establishment as a liturgical feast of Corpus Christi. It was instituted on September 8, 1264 by Pope Urban IV, through the bull Transiturus hoc mundo. St. Thomas Aquinas is charged with preparing the texts for the Office and Mass of the day, which includes hymns and sequences, such as Pange Lingua (and its final part Tantum Ergo), Lauda Sion, Panis angelicus, Adoro te devote or Verbum Supernum Prodiens.
In the Council of Vienne of 1311, Clement V will give the rules to regulate the processional procession inside the temples and even indicate the place that should occupy the authorities who would like to be added to the parade.
In the year 1316, John XXII introduced the Eighth with an exposition of the Blessed Sacrament. But the great accolade will be given by Pope Nicholas V, when on the feast of Corpus Christi in 1447, he goes out processionally with the Holy Host through the streets of Rome.
In many places it is a party of special relevance. In Spain there is the popular saying: Three Thursdays there are in the year that shine more than the sun: Holy Thursday, Corpus Christi and the day of Ascension, which gives an idea of the roots of this festival.
The celebrations of the Corpus usually include a procession in which the same Body of Christ is exhibited in a monstrance.
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