It was the feast of Corpus Christi earlier this week; I had the privilege of presiding at Communion on the day. Corpus Christi goes back to the thirteenth century, in part due to the lobbying of a Belgian religious who after her death was canonised- St. Juliana of Liege.
The central notion of the day is to give thanks for the service of the Eucharist, or Holy Communion; it is more usually remembered as part of the events of Holy Week. Juliana's thesis was that its place can be somewhat overlooked in the rush of events leading to Jesus' trial and execution. Hence a day where it stands by itself, and due consideration can be given to its 'weight'.
As a priest, I see people's faces as they take communion. Few others do. I have written before of the devotion of older folk who at pain to themselves, will kneel to receive the bread and wine; the struggle of some disabled folk to come to the altar rail to receive. I have no idea what goes on in people's hearts and minds as they eat the morsel of bread, take the sip of wine, but I sense their thankfulness, their love, their devotion, to this simple but profound act and its meaning.
'I am the bread of life' says Jesus in the gospel reading for Corpus Christi. To see the faces of the believers on that day was to believe it.