70 Even before He ate the Last Supper with His disciples Christ Our Lord, since He knew He was about to institute the sacrament of His body and blood by the shedding of which the new covenant was to be consecrated, felt His heart roused by strong emotions, which He revealed to the Apostles in these words: "With desire have I desired to eat this Pasch with you before I suffer."(71) And these emotions were doubtless even stronger when "taking bread, He gave thanks, and broke, and gave to them, saying, 'This is My body which is given for you, this do in commemoration of Me.' Likewise the chalice also, after He had supped, saying, 'This chalice is the new testament in My blood, which shall be shed for you.'"(72)
Source: Haurietis Aquas (Vatican.va)