Transubstantiation was named a thousand years after the Last Supper
Catholic teaching holds that at Mass the whole substance of bread and wine becomes Christ's body and blood while taste, colour and texture stay exactly the same. The New Testament never uses the word. It first appears in the late 11th century, and a church council adopted it only in 1215.
The doctrine rests on a distinction between substance, what a thing fundamentally is, and accidents, its outward appearances. Official teaching calls the change a mystery beyond understanding and insists the terms are not tied to any single system of metaphysics. Its scriptural roots lie in what Jesus said over the bread and cup at the Last Supper, identifying them with his body and blood, together with the account Paul passed on in 1 Corinthians 11. By the middle of the 1st century, Christians were already sharing a loaf and cup as a regular practice.
Early writers used vivid language without defining how the presence worked. Ignatius of Antioch, around 106, called the bread the flesh of Christ, and Justin Martyr, around 150, contrasted the consecrated food with common bread. Clement of Alexandria and Tertullian spoke of symbols and figures, but in that Platonist world a symbol could make present what it signified. Ambrose of Milan was blunter: bread before the words of consecration, the body of Christ after.
The medieval West forced the question. Around 831 Paschasius Radbertus, abbot of Corbie, argued that because God is truth itself, Christ's words must be taken literally. In the 11th century Berengar of Tours denied that any material change was needed, and the quarrel pushed theologians to be precise. Hildebert de Lavardin, archbishop of Tours, is the first known to use the term, and by the close of the 12th century it was common. The Fourth Lateran Council declared the bread and wine transubstantiated in 1215, and Thomas Aquinas later gave the idea its classic philosophical form using Aristotle.
Other traditions describe the same sacrament differently. Lutherans speak of a sacramental union, the Reformed tradition teaches a spiritual presence, and Eastern Orthodox writers prefer words like change or trans-elementation; the Greek metousiosis was coined as a direct translation only in the 17th century. John Wycliffe was among the 14th-century reformers who challenged the doctrine.
Source: Transubstantiation
