text: However, at least until the time of Luther, there was general agreement on the usefulness of the Aristotelian definitions as a way of understanding the mechanism by which the transformation of the bread and wine into the body and blood of Christ was done. In 1551, the Council of Trent reaffirmed transubstantiation with the statement: "This change [of bread and wine into body and blood] has conveniently and appropriately been called transubstantiation by the holy catholic church."