Transubstantiation

Abstract Christians have held from earliest times that Jesus, since his resurrection from the dead, is present as the risen Lord in the community. Christians claim that this presence makes itself felt powerfully in the ritual meal of blessed bread and wine known as the Eucharist or Lord's Supper. In the 11th century Christian writers began to discuss in earnest how this presence in the Eucharist might be possible. Transubstantiation emerged from these discussions as one way of describing how this might occur. Most basically, transubstantiation posits that the substantia (substance) of the bread and of the wine is replaced by the substantia of the body and of the blood of the risen Lord during the blessing of the bread and wine in the ritual of the Eucharist. Substantia although not understood in the same way by all medieval theologians, generally referred to the Aristotelian category of “ ousia ” or the essential reality that underlies individual things. Transubstantiation and a belief in the real presence, although sometimes confused, are quite distinct. Belief in the real presence asserts that the risen Lord is present in the Eucharist; transubstantiation attempts to explain how that is possible. Belief in the real presence was considered a requirement for orthodox Christian belief among most Christian groups. It is not clear that transubstantiation was ever so required by any Christian group, except when denial of transubstantiation was understood to entail denial of the real presence.