|(St. Vincent Ferrer Parish, NYC)|
That the real Body and Blood of Christ is present in the Sacrament is something that cannot be perceived either with the senses or with the intellect, but only with faith, which is supported by the authority of God. Because of this, when commenting on the passage in Luke 22:19: "This is my body which is given up for you," St. Cyril says: "Do not cast doubt on the truth of this, but rather accept with faith the words of the Savior: because He, being the Truth, does not lie."
St. Thomas Aquinas, S. Th., III, q. 75, a.1