The Fourth Lateran Council: transubstantiation and obligatory confession

The Fourth Lateran Council (1215), convened by Innocent III, gave in canon 1 the first official definition of transubstantiation: the body and blood of Christ are truly contained in the sacrament of the altar under the appearance of bread and wine, the bread being transubstantiated into the body and the wine into the blood by divine power, and only a duly ordained priest can perform the sacrament. The council also required all the faithful to confess to a priest and to receive communion at least once a year, and protected the seal of confession. Thomas Aquinas developed the doctrine by means of the Aristotelian distinction between substance and accidents: the substance of bread and wine is wholly converted, while the outward properties remain. In 1379–1380 Wyclif rejected transubstantiation as a recent innovation, philosophically incoherent and contrary to Scripture.