The Eucharistic Miracles of the World (Catalogue of the Vatican International Exhibition)

Those who behold the Sacrament of the Eucharist, consecrated by the priest, but only see the appearances of bread and wine, and do not believe by the grace of the Spirit that these are really the Body and Blood of Christ, condemn themselves, since they do not believe the testimony of the Lord Himself who said, 'This is my Body and Blood of the new covenant,' and promises, 'Whoever eats my Flesh and drinks my Blood has eternal life" (Jn 6:56) - St Francis of Assisi