Transubstantiation

When I was in diaconate formation, we were taught (many times!) never to use big, complicated theological words in our homilies. This column, however, is fair game to discuss one of the most important and central concepts of our Catholic faith: transubstantiation.

If we look at the etymology of the word, it literally means “to change from one substance to another.” The bread and wine consecrated by the priest on the altar, we believe, actually becomes the Body, Blood, Soul and Divinity of Jesus Christ himself.

The first official use of this term as doctrine occurred at the Fourth Lateran Council in 1215, though it had been in use about a century before. As with all things we believe, there is a Scriptural basis for this, found in 1 Cor. 11:23-27, as well as the Gospel accounts of the institution of the sacrament (for example, Lk. 22:7-20). This mystery is critical to our Catholic faith.

One of my favorite saints, Thomas Aquinas, explained this using philosophy (in terms borrowed from Aristotle) and metaphysics. He termed the bread and wine itself the “substance,” meaning that which exists in its own right, without needing to be sustained by another. The outward appearances of the bread and wine are the “accidents” (not meaning “oops” but that which could change, like color or shape). In his work Summa Theologiae (III, q.75, a.2), he stated that the substance must become Christ and ceases to be bread and wine. This is because Jesus himself said of the Eucharist, “This is my body. This is my blood.” It still looks, tastes and smells like bread and wine (the “accidents” remain). But it now truly is Jesus, his Real Presence. Jesus is not present along side the bread and wine (consubstantiation) but is the bread and wine.

However strong the help of reason might be, transubstantiation is still ultimately a matter of faith. And this doctrine is foundational to what it means to be Catholic.

“By the consecration the transubstantiation of the bread and wine into the Body and Blood of Christ is brought about. Christ himself … is present in a true, real and substantial manner.” - Catechism of the Catholic Church, 2nd ed., n. 1413