This Eucharistic miracle, whose relic is still preserved in the Benedictine Monastery of Andechs, Germany, is verified by numerous written sources. The authentication took place in Rome in 595 during a Eucharistic celebration presided by Pope St. Gregory the Great. At the moment of receiving Holy Communion, a Roman noblewoman began to laugh because she had doubts about the Real Presence of Christ in the consecrated Bread and Wine. The Pope, troubled by her disbelief, decided not to give her Communion and then the Bread turned into Flesh and Blood.
Among the most important works in which this Eucharistic miracle that occurred in Rome in 595 is mentioned, is Vita Beati Gregorii Papae written by Deacon Paul in 787. It was customary in those times to have the Eucharistic bread prepared by the parishioners.
Pope St. Gregory the Great was a direct eyewitness to this prodigy. One Sunday, while celebrating the Sacred Mass in an ancient church dedicated to St. Peter, the Pope was distributing Communion and saw among the faithful in line, one of the women who had prepared the bread for the consecration and she was laughing out loud. Troubled, the Pope cornered her and asked her to explain her behavior. She justified herself by saying that she could not believe that the bread she made with her very own hands could become the Body and Blood of Christ during the consecration.