Scripture, Tradition and the Magisterium are so closely united with each other that one of then cannot stand without the others. Working together, each in its own way, under the action of the one Holy Spirit, they all contribute effectively to the salvation of souls.
Ref. CCC 95
Taken From The Compendium - Catechism Of The Catholic ChurchRead More
At the Last Supper with his apostles on the eve of his passion Jesus anticipated, that is, both symbolized his free self-offering and made it really present: “This is my Body which is given for you” (Luke 22:19), “This is my Blood which is poured out...” (Matthew 26:28) Thus he both instituted the Eucharist as the “memorial” (1 Corinthians 11:25) of his sacrifice and instituted his apostles as priests of the new covenant. Please click here to learn more about Holy Mass, also known as the celebration of the Holy Eucharist.