The sacrificial nature of the Mass, solemnly defended by the Council of Trent,
because it accords with the universal tradition of the Church, was once more stated by the Second Vatican Council, which pronounced these clear words about the Mass: ‘At the Last Supper, Our Savior instituted the Eucharistic Sacrifice of his Body and Blood, by which the Sacrifice of his Cross is perpetuated until he comes again; and till then he entrusts the memorial of his Death and Resurrection to his beloved spouse, the Church’  - GIRM #2