According to ancient tradition, the Church of Jerusalem celebrated Corpus Christi, which is one of the most important solemnities celebrated at the Basilica of the Resurrection.
It is the feast of the real presence of Jesus Christ in the Eucharist, which reminds us of the importance of this sacrament and of Christ’s gift, offered as a sacrifice for us. This solemnity, which was a local tradition in Belgium in 1247, was placed in the liturgical calendar for the Universal Church a little less than 800 years ago, in 1267, by Pope Urban IV. This occurred at a time when the doctrine of the real presence of Christ in the Eucharist was being heavily doubted. This was explained by the Apostolic Administrator of the Latin Patriarchate in his homily during the solemn mass for the feast.
Beginning on the previous day, however, celebrations at the Holy Sepulcher had already begun. The Franciscan friars of the Custody of the Holy Land on the vigil of the feast of Corpus Christi went to the Latin Patriarchate to invite the Apostolic Administrator of the Latin Patriarchate to make his solemn entry into the Sepulcher. In the early afternoon, before the Holy Edicule, they celebrated the first Vespers for the feast. Then came the time for the daily solemn version of the procession at the Holy Sepulcher, with the presence of the Blessed Sacrament, at the very place where the Body of Christ was laid and where he rose.