At every celebration of the Eucharist or Communion Service, the celebrant holds up the consecrated host and echoes the words of John the Baptist, but with a slight change! The "sin of the world" becomes the "sins" of the world. In the Gospel According to John, the "sin of the world" would be a failure to recognize Jesus as the Son of God. The text in the Eucharist seems to take in more than that - the whole of human experience in its many failures! What can be important, however, is our response. We echo the words of the pagan centurion when we say, O Lord, I am not worthy..... Our response does not end with that, however. When we receive the Body of the Lord, the celebrant says to us: "The Body of Christ!" and we respond, "AMEN!" I have to admit that sometimes I have to be a lip reader to hear that "AMEN!" And some folks just don't say anything. John the Baptist's testimony becomes our own when we say that AMEN!
During the COVID epidemic, the desire of the faithful to "receive communion" became evident and there were a lot of creative logistics [parking lot drive-by, etc.] to make that possible. The Act of Spiritual Communion was dusted off to assure the faithful that the same spiritual benefit could be available if they were unable to receive communion in person. We Catholics have many ways of showing that we are "Catholic!" The Sign of the Cross, the rosary, processions - these are public testimonies. It is easy to forget the significance of the "AMEN!" we are called to say when we receive the Body of the Lord. It's just one word, but it encompasses all of our Catholic faith! AMEN