The festival of Corpus Christi celebrates the Eucharist as the body of Christ. The name 'Corpus Christi' is Latin for 'the body of Christ'.
This jubilant festival is celebrated by Roman Catholics and other Christians to proclaim the truth of the transubstantiation of bread and wine into the actual body of Christ during Mass.
In some countries in the world, Catholic churches still celebrate the festival, not only with a Mass, but also with a procession that carries the consecrated wafer through the streets as a public statement that the sacrifice of Christ was for the salvation of the whole world.
Corpus Christi falls between late May and the middle of June, on the first Thursday after Trinity Sunday (60 days after Easter). In some countries the festival is celebrated on the Sunday after Trinity Sunday.
The festival was inspired by the religious experience of St Juliana (1193-1258), a Belgian nun, who dreamed repeatedly of the Church under a full moon with a black spot.
According to legend, the dream was interpreted to her in a vision by Christ. The moon, she said, was the Church's calendar of festivals and the black spot was the lack of a festival to celebrate the holiest element of the Church - the Eucharist.
Juliana shared this with her local bishop, who in 1246 issued a decree for such a festival to be celebrated in his territory.
The festival was instituted throughout the Church by Pope Urban IV in 1264. Before that there had been no universal festival to mark the sacrament of the Eucharist.
Corpus Christi was made an obligatory feast for Roman Catholics by Pope Clement V in 1311 at the Council of Vienne.
In 1551, the Council of Trent described the festival as a 'triumph over heresy'. They meant by this that when Christians celebrated the festival they affirmed their belief in the doctrine of transubstantiation, and thus the victory of the Church over those heretics who denied that the consecrated wafer became the real body of Christ during the Mass.
The festival has a particular resonance for Spain and Portugal, and countries in Latin America. In Seville the festival was known as 'the Thursday that shines greater than the sun'.
In such countries the festival is popular and elaborate. The triumphal nature of the celebration is acted out by treating the sacred host almost as if it were a military hero returning in victory from the wars - the host may be carried on a cart (representing a chariot) through crowds and beneath triumphal arches erected for the event.
Historically, the festival was accompanied by music, dancing and fireworks.
Painting: The Corpus Christi (1855) by Alexandre Antigna (France; 1817-1878)
Source: https://archive.ph/mtx5q#selection-797.0-805.75