I understand the Church’s teaching on Eucharist. Transubstantiation means it changes completely from bread and wine to the flesh and blood of Jesus. I believe in the Eucharist, the source and summit of our faith. I also understand that our senses cannot tell the difference. Therefore, why are gluten-free hosts needed?
Thanks for asking. The Church’s teaching on transubstantiation, officially taught at Lateran Council IV in 1215, uses scholastic philosophy’s distinction between substance (what something really is, its essence) and accidents (what is variable within the same substance). The Catholic Church believed in the Real Presence long before the term transubstantiation was officially approved.
At Mass, the substance of the bread is changed into the substance of Christ’s body. The same is true of the wine.
The accidents such as taste, smell, weight, and color, however, remain the same. According to this terminology, gluten is an “accident. ” The host that had gluten before it was consecrated will still have gluten after it is consecrated. Likewise, the alcoholic content of wine remains the same after it is consecrated during Mass.
A person with celiac disease needs a gluten-free host because consecration at Mass does not remove gluten. Devout faith in the Eucharist by a person with celiac disease will not change how her or his body reacts to a gluten host received in holy Communion. This explains the need that some Catholics have for a gluten-free host.
Sections 1373–77 of the Catechism of the Catholic Church explain the Church’s understanding of transubstantiation in greater detail.