Holy Eucharist Teachings by the Fathers of the Church
"How can this come about?" Mary asked. "The Holy Spirit will come upon you," the angel answered, "and the power of the Most High will cover you with its shadow." And now you are the one who puts the question: "How can bread become Christ and wine His Blood?" I answer: "The power of the Holy Spirit will be at work to give us a marvel which surpasses understanding."
Holy Eucharist teachings by the Fathers of the Church - St. John Damascene