The feast of the Most Holy Body and Blood of Christ, still often referred to by its shorter Latin name of Corpus Christi, has benefited in recent years from its transfer from the first Thursday after Trinity Sunday to the Sunday of the following week, as well as from the revival of popular piety in the West.
This means that each June Corpus Christi processions have once again become a feature of the life of many parishes, permitting the faithful not only to deepen their love for Christ in the Eucharist but also showing the public something of what it means to be a Catholic.
When walking in procession Catholics might mentally throw themselves at the feet of Our Lord, recalling the actions of the crowds on the first Palm Sunday, offering prayers, words of praise and thanksgiving, and atonement for their sins and those of the world, for the failure to appreciate the gift of the Eucharist and for the outrages committed against Jesus. Pray also for any onlookers.
But if you come across a procession by accident, then kneel as the Eucharist passes by. This kind of public witness to the Real Presence has led many non-Catholics into the Church.