The noblest sacrament, consequently, is that wherein His Body is really present. The Eucharist crowns all the other sacraments.
- St. Thomas Aquinas: Disputations concerning Truth, 27, 4.
Christ's true Body, born from the Virgin Mary, is contained in the Sacrament of the Altar. To profess the contrary is heresy, because it detracts from the truth of Scripture, which records our Lord's own words, This is My body (Matth. 26, 26).
St. Thomas Aquinas: Commentary on the Sentences, 4, 10, 1.
That Christ's true Body and Blood are present in this Sacrament can be perceived neither by sense nor by reason, but by faith alone, which rests on God's authority.
St. Thomas Aquinas: Summa Theologica, 3, 75, 1.
It is evident to the senses that all the accidents of bread and wine remain after consecration. Such is the reasonable course of divine Providence, for it is abominable to eat human flesh and drink human blood. That is why Christ's Body and Blood are offered to us under the species of what we are accustomed to take, namely, bread and wine.
St. Thomas Aquinas: Summa Theologica, 3, 75, 5.
0 God, Who in this wonderful Sacrament hast left us a memorial of Thy passion, grant us, we beseech Thee, so to venerate the sacred mysteries of Thy Body and Blood, that we may ever perceive within us the fruit of Thy redemption.
Roman Missal, Collect for Corpus Christi. St. Thomas Aquinas.