From the Breviary of Prague, 1502, the continuation of the Bull “Transiturus” of Pope Urban IV, promulgating the feast of Corpus Christi, read in the Divine Office for the lessons of Matins during the octave.
The Adoration of the Eucharist, by Jerónimo Jacinto Espinosa, 1650
Because in the feasts (of the Saints) some faults are committed against their due solemnity, whether by negligence, or engagement in familial matters, or else through human frailty, Mother Church has appointed a certain day for a general commemoration of all the Saints, so that in this common celebration, whatever was lacking in their individual festivities may be done rightly. Therefore, we ought especially to do the same thing regarding this life-giving sacrament of the Body and Blood of Jesus Christ, who is the glory and crown of all the Saints, so that it may shine before us with a special festivity and celebration, and so that whatever was perhaps omitted in the other celebrations of the Mass regarding its solemnity may be made good with devotion and diligence. ...
When we were in a lesser office, most beloved, we learned that it was divinely revealed to certain Catholics that such a feast ought to be generally celebrated. Therefore, for the strengthening and exaltation of the Catholic faith, we have deemed it worthy and reasonable to decree that a special and more solemn yearly memorial of so great a sacrament should be celebrated, apart from the daily commemoration which the Church makes thereof; and we designate and appoint a certain day for this purpose, to wit, the first Thursday after the octave of Pentecost, so that on that day, the faithful may with devotion and affection come to the churches, and both the clergy and people rejoicing together may rise up in songs of praise.
The Adoration of the Eucharist, by Jerónimo Jacinto Espinosa, 1650
