The Solemnity of the Most Holy Body and Blood of Christ — commonly known as Corpus Christi (Latin for 'Body of Christ') — is a feast celebrating the Real Presence of Jesus Christ in the Eucharist. It is celebrated on the Thursday (or in some countries, the Sunday) after Trinity Sunday. The feast was instituted by Pope Urban IV in 1264 through the bull Transiturus de hoc mundo, largely inspired by the Eucharistic miracle at Bolsena (1263), in which a consecrated host bled onto a corporal cloth during Mass celebrated by a priest who doubted the Real Presence. The great theologian St. Thomas Aquinas composed the liturgical texts for the feast, including the beloved hymns Pange Lingua, Tantum Ergo, and O Salutaris Hostia. A hallmark of the celebration is the Eucharistic procession: the Blessed Sacrament, displayed in a monstrance, is carried through the streets while the faithful sing hymns, strew flower petals, and adore Christ publicly. Corpus Christi is a profound public witness to Catholic belief in the Real Presence and an invitation to deepen Eucharistic devotion.