Cyril of Jerusalem (A.D. 350) - Catechetical Lectures On the Mysteries IV, On the Body and Blood of Christ, 22:6,9:

"Do not, therefore, regard the bread and wine as simply that, for they are, according to the Master's declaration, the body and blood of Christ. Even though the senses suggest to you the other, let faith make you firm. Do not judge in this matter by taste, but be fully assured by faith, not doubting that you have been deemed worthy of the body and blood of Christ. . . [Since you are] fully convinced that the apparent bread is not bread, even though it is sensible to the taste, but the body of Christ, and that the apparent wine is not wine, even though the taste would have it so. . . partake of that bread as something spiritual, and put a cheerful face on your soul"