when does the bread and wine become the body and blood
Transubstantiation Transubstantiation (in Latin, transsubstantiatio, in Greek μετουσίωσις metousiosis) is, according to the teachings of the Catholic Church, the change of substance by which the bread and wine offered in the sacrifice of the sacrament of the Eucharist during the Mass, become, in reality, the body and blood of Jesus.