Because Easter was so early this year, all of the other liturgical feasts have come up very fast as well, including this one. The Feast of Corpus Christi is celebrated the Thursday after Trinity Sunday, two weeks after Pentecost. In the United States, the feast is always transferred to the following Sunday. Since Pentecost is always 50 days after Easter, we have the rare occurrence of celebrating Corpus Christi in May instead of June! It will be in May in 2018 and then again not until 2024.
The actual feast is very old, dating from 1246, and celebrated by the universal church under Pope Urban IV in 1264. The Office and the Mass for this date were written by the great Thomas Aquinas.
Interestingly the Old testament priest, Melchezidek plays a more significant role in the mass on this day. Usually only mentioned in the first ( and long) Eucharistic prayer, he gets a proper mention in the Psalm response for the Feast of Corpus Christi.
Priests are encouraged to hold Eucharistic Processions for the faithful on this date. My current pastor is the only priest in my lifetime who has ever done so, and I appreciate the beauty, history and significance of this every year. Hopefully the weather will cooperate with us again this year.
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